Consulta: subjectFacets:"Photosynthesis"
Registros recuperados: 220
Data/hora: 05/06/2024 12:28:19

Tolerancia a salinidad de tomate injertado
Provedor de dados: 32
Autores: Orosco Alcalá, Blanca Estela.
La presente investigación se llevó a cabo en la empresa Vegetales de  Teotihuacan S. A de C. V. ubicada en Teotihuacan, de agosto a diciembre de  2007. Se estudió el efecto de los injertos de tomate Maxifort (MX), Multifort (MF),  Beaufort (BF) y de cuatro concentraciones de NaCl (0, 50, 100 y 150 mM)  suministradas en la solución nutritiva Steiner sobre la altura de planta, diámetro  de tallo, fotosíntesis, rendimiento, peso fresco y seco, calidad de fruta,  concentración nutrimental y contenido de prolina en hojas. Se utilizó el híbrido  Caimán sobre los portainjertos y éste mismo se usó como control (NI). Los  resultados indican una disminución de altura de planta, diámetro de tallo,  fotosíntesis y rendimiento, al aumentar el NaCl en la solución...
Tipo: Tesis
Palavras-chave: Lycopersicon esculentum Mill.; Portainjertos; Prolina; Fotosíntesis; Rendimiento; Maestría; Edafología; Rootstocks; Proline; Photosynthesis; Yield.
Ano: 2008
URL: http://hdl.handle.net/10521/1320

Análisis bioquímicos y moleculares de la biosíntesis de carotenos en diferentes tejidos de maíz.
Provedor de dados: 32
Autores: Silva Pérez, Viridiana.
El maíz (Zea mays L.) es el cultivo básico más importante en México, y en los últimos años se ha secuenciado su genoma. En este trabajo se utiliza parte de la información genómica, 2,039 marcadores moleculares y se relaciona con el contenido de carotenos en líneas endogámicas recombinantes de maíz de la cruza B73 × Mo17  (IBM-RILs) para detectar loci de caracteres cuantitativos (QTLs). En la primera fase, se estudió el contenido de carotenos en las hojas, ya que éstos disipan la energía lumínica utilizada en la fotosíntesis, influyendo así en la tasa fotosintética y en el rendimiento de los cultivos. Se midió el contenido de luteína, β-caroteno, α-caroteno, β-criptoxantina y zeaxantina, y se encontró que β-caroteno representó 80% del total de carotenos. Se...
Palavras-chave: Zea mays; Follaje; Grano; Fotosíntesis; Provitamina A.; Foliage; Kernel; Photosynthesis; Pro-vitamin A; Maestría; Genética.
Ano: 2011
URL: http://hdl.handle.net/10521/450

Respuesta fisiológica de lineas de frijol tolerante y susceptible a clorosis férrica
Provedor de dados: 32
Autores: Zavala Estrada, Fabiola.
La clorosis por deficiencia de hierro (Fe) es un estrés abiótico encontrado principalmente en  cultivos que crecen en suelos calcáreos o alcalinos (Rombolà y Tagliavini, 2007). Como  resultado de la deficiencia de Fe se altera la morfología y fisiología de las plantas (Bertamini  y Nedunchezhian, 2005). Se determinaron algunos cambios anatómicos en hojas jóvenes y  fisiológicos en la raíz de plantas de frijol (Phaseolus vulgaris L.) tolerante y susceptible a  clorosis férrica que ocurren cuando éstas se someten a estrés de hierro para identificar la  respuesta diferencial de las dos líneas en estas condiciones. En la hoja clorótica de la línea  tolerante la estructura del mesófilo se mostró organizada pero, con el parénquima esponjoso  más compactado y con...
Tipo: Tesis
Palavras-chave: Phaseolus vulgaris; Deficiencia de hierro; Cloroplastos; Fotosíntesis; Concentración nutrimental; Maestría; Phaseolus vulgaris; Iron deficiency; Chloroplasts; Photosynthesis; Nutrimental concentration.
Ano: 2009
URL: http://hdl.handle.net/10521/1314

Análisis bioquímicos y moleculares de la biosíntesis de carotenos en diferentes tejidos de maíz.
Provedor de dados: 32
Autores: Silva Pérez, Viridiana.
El maíz (Zea mays L.) es el cultivo básico más importante en México, y en los últimos años se ha secuenciado su genoma. En este trabajo se utiliza parte de la información genómica, 2,039 marcadores moleculares y se relaciona con el contenido de carotenos en líneas endogámicas recombinantes de maíz de la cruza B73 × Mo17  (IBM-RILs) para detectar loci de caracteres cuantitativos (QTLs). En la primera fase, se estudió el contenido de carotenos en las hojas, ya que éstos disipan la energía lumínica utilizada en la fotosíntesis, influyendo así en la tasa fotosintética y en el rendimiento de los cultivos. Se midió el contenido de luteína, β-caroteno, α-caroteno, β-criptoxantina y zeaxantina, y se encontró que β-caroteno representó 80% del total de carotenos. Se...
Palavras-chave: Zea mays; Follaje; Grano; Fotosíntesis; Provitamina A.; Foliage; Kernel; Photosynthesis; Pro-vitamin A; Maestría; Genética.
Ano: 2011
URL: http://hdl.handle.net/10521/450

Sombra artificial y aplicación de thidiazurón en el crecimiento y fisiología de la vainilla (Vanilla planifolia Andrews).
Provedor de dados: 32
Autores: Olivares Soto, Héctor Miguel.
El objetivo de esta investigación es documentar el efecto de diferentes niveles de sombra artificial y la aplicación de TDZ sobre el número y crecimiento de brotes laterales, en la producción y distribución de la materia seca en la planta de vainilla así como el efecto en parámetros fisiológicos del intercambio de gases. Para ello, se trabajó con esquejes de vainilla, con ocho yemas. Los  niveles de sombra fueron 30, 50 y 70 %  y  0, 500  y 1000 mg-litro-1 de Thidiazurón. Se midió longitud  y diámetro de brotes, número de hojas, tasa de fotosíntesis aparente (FA), transpiración (Tr), conductancia estomática (CE), concentración intercelular de CO2 (CINT), área foliar total por planta y la distribución de peso seco a en los componentes de la planta.  No hubo...
Palavras-chave: Vanilla planifolia A.; Regulador de crecimiento; Longitud de brote; Intercambio gaseoso; Area foliar; Fotosíntesis; Materia seca; Vanilla planifolia Andrews; Growth regulator; Shoot length; Gas exchange; Total upper leaf surface; Photosynthesis; Dry mass; Maestría; Fruticultura.
Ano: 2010
URL: http://hdl.handle.net/10521/252

Leaf concentrations of nitrogen and phosphorus in phaseolus vulgaris l. Plants under high CO2 concentration and drought stress
Provedor de dados: 70
Autores: Silva,João B. L. da; Ferreira,Paulo A.; Justino,Flávio; Pires,Luanna C.; Toledo,Amanda S.
This study aims to evaluate the leaf concentration of nitrogen and phosphorus correlated to the production of photoassimilates in beans plants (Phaseolus vulgaris L.) under high [CO2] and drought stress. The experiment was conducted in Viçosa (Brazil), during the period from April to July 2009, by using open-top chambers equipped with CO2 injection system. The drought stress was applied, through the irrigation suspension, during the period from flowering to maturation. The experimental design was randomized blocks in split-plot scheme with four replication, where the plots with plants grown in [CO2] of 700 mg L-1 and [CO2] environment of 380 mg L-1 and the subplots with plants with and without drought stress. The results were submitted to ANOVA and Tukey...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Beans; Mineral nutrition; Photosynthesis; Climatic changes.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162014000500012

Cloroplast pigments as indicators of lead stress
Provedor de dados: 70
Autores: Gomes,Silvânia M. de S.; Lima,Vera Lucia A. de; Souza,Adailson P. de; Nascimento,Joab J. V. R. do; Nascimento,Everaldo S. do.
Plants respond to environmental adversities, becoming an indicator for assessing the environment quality. In this aspect, chlorophyll contents as well, carotenoids are used as a reliable indicator to associate environmental quality and pollution, mainly regarding the toxicity of heavy metals in higher plants. So, we aimed to evaluate the content of chlorophyll a, b, and total chlorophylls and carotenoids in plants vetiver [Vetiveria zizanioides (L.) Nash], maize (Zea mays L.) cv. AG 1051, sunflower (Helianthus annuus L.) cv. BRS 122/V-2000, and castor beans (Ricinus communis L. ) cv . Northeastern BRS grown in contaminated soil with lead, with and without correction of soil pH, so they were used as indicators of metal stress by the soil. From the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Heavy metal; Pollution; Photosynthesis.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162014000500007

EFFECT OF THE MIST MICRO-SPRAY TIME ON PHOTOSYNTHETIC SPATIAL HETEROGENEITY OF GRAPE CANOPY
Provedor de dados: 70
Autores: Zheng,Ming; Bai,Yungang; Zhang,Jianghui; Liu,Hongbo; Ding,Ping.
ABSTRACT In grape, high temperatures and low humidity prolong midday depression of foliar photosynthesis and dramatically reduce fruit yield. In this study, we explored the effects of various mist micro-spray treatments on grape photosynthesis at a test site in Shanshan County (N, 42.91°; E, 90.30°), Turpan, Xinjiang, China. We tested four different mist micro-spray durations including 1 h (WP1), 2 h (WP2), 3 h (WP3), and 0 h (CK). WP1, WP2, and WP3 affected canopy air temperature and humidity for 5 h, 7 h, and 9 h, respectively. At 12:30, WP1, WP2, and WP3 had the strongest cooling effect and altered temperature by −5.12 °C, −5.09 °C, and −5.17 °C respectively. The relative chlorophyll content was higher in the upper than the lower canopy leaves. There...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Air temperature; Chlorophyll; Photosynthesis; Stomatal conductance; Transpiration rate.
Ano: 2021
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162021000100039

Influences of two CO2 concentrations and water availability on bean crop
Provedor de dados: 70
Autores: Silva,João B. L. da; Ferreira,Paulo A.; Pires,Luanna C.; Pereira,Eduardo G.; Carneiro,José E. S.
This study was carried out to determine some physiological and phenological responses of the bean under high [CO2] and drought stress. The experiment was conducted from April to July 2009 in Viçosa, Brazil. The open-top chambers were used to enrich the air with CO2, whereas the drought stress was applied between the flowering and the ripening. The randomized block design was used, with four replicates in the subplots. The following plots were [CO2] at 700ppm (F1) and [CO2] environmental (F2) and the subplots were well watering (S1) and drought stress (S2). The results were subjected to Anova and the Tukey test (P &lt; 0.05). For the treatments F1S1 and F1S2 the photosynthetic rate showed increments of 59% and the transpiration reduction of 12%. The yield,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Phaseolus vulgaris L.; Climate changes.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000400012

Fruit yield and gas exchange in bell peppers after foliar application of boron, calcium, and Stimulate
Provedor de dados: 75
Autores: Zeist,André R; Zanin,Daniel S; Camargo,Cristhiano K; Resende,Juliano TV de; Ono,Elizabeth O; Rodrigues,João D.
ABSTRACT The objective of this study was to evaluate the effect of the isolated and combined foliar application of boron, calcium, and the plant growth regulator Stimulate on fruit yield and gas exchange in bell peppers. The evaluated treatments were boron, calcium, Stimulate, boron + calcium, boron + Stimulate, calcium + Stimulate, boron + calcium + Stimulate, and control (water). The study was performed in complete randomized block design with three replicates. The applications were performed biweekly on the plant leaves from the beginning of flowering (December 21, 2013) until March 1, 2014. The analyzed gas exchange characteristics were photosynthetic yield, internal CO2 concentration, and transpiration rate. The evaluated agronomic characteristics...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Capsicum annuum; Leaf fertilizer; Photosynthesis.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362018000400498

Compatibility of tomato cultivar Santa Cruz Kada grafted on different Solanaceae species and control of bacterial wilt
Provedor de dados: 75
Autores: Zeist,André R; Giacobbo,Clevison L; Silva Neto,Gentil F da; Zeist,Ricardo A; Dorneles,Keilor da R; Resende,Juliano TV de.
ABSTRACT The objective of this work was to evaluate the compatibility, gas exchange and yield of tomato cultivar Santa Cruz Kada, susceptible to bacterial wilt (Ralstonia solanacearum) when grafted on different Solanaceae species. Rootstock sources were the mini-tomato RVTC-66, Cayenne pepper, Jerusalem cherry (Solanum pseudocapsicum), sticky nightshade (Solanum sisymbriifolium), and cultivar Santa Cruz Kada itself (self-grafting). Two materials were tested to promote the union between rootstocks and scions: grafting clips and biodegradable tape (Parafilm). Grafting success index (GSI) was evaluated and, for treatments using biodegradable tape, grafting incompatibility, gas exchange, agronomic characteristics and bacterial wilt epidemiology were assessed...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Solanum lycopersicum; Ralstonia solanacearum; Photosynthesis; Grafting; Production.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362018000300377

Gas exchange in gariroba palms grown under subtropical conditions
Provedor de dados: 75
Autores: Modolo,Valéria A; Erismann,Norma M; Tucci,Maria LS.
ABSTRACT Gariroba palm, native to Brazil, produces bitter heart-of-palm, consumed as vegetable in salads, as well as in other Brazilian recipes. This research was carried out in field condition to evaluate diurnal and seasonal variation of gas exchange of gariroba palms cultivated under subtropical conditions, considering their interrelation with some climate elements. Plants were evaluated within two consecutive years, grown under field conditions and irrigated, spaced 2x1 m. Net assimilation of CO2 (PN), stomatal conductance (g s ), transpiration (E), leaf temperature (T l ) within the chamber and the photosynthetic photon flux density (PPFD) were evaluated. Water use efficiency (WUE) was estimated by the ratio: WUE = PN/E. Net CO2 assimilation (PN),...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Syagrus oleracea; Photosynthesis; Bitter heart-of-palm.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362018000200211

Subirrigation automated by capacitance sensors for salvia production
Provedor de dados: 75
Autores: Ferrarezi,Rhuanito S; Iersel,Marc W van; Testezlaf,Roberto.
Subirrigation is typically controlled using timers to periodically irrigate plants based on a pre-determined schedule. The objective of this study was to evaluate the usefulness of capacitance-type sensors to monitor substrate water content and to control subirrigation automatically for salvia production in greenhouse. Additionally, we quantified the effect of different substrate volumetric water content (VWC) on growth of plants cultivated in 15-cm diameter × 13.75-cm height pots. Automation was performed using three EC-5 capacitance soil moisture sensors per experimental unit, connected to a system with a CR10X data logger, AM16/32 multiplexer, SDM-CD16AC relay driver and NK-2 submersible pumps. Substrate moisture readings were taken every 15 minutes,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Salvia splendens 'Vista Red'; Automation; Ebb-and-flow benches; Photosynthesis; Plant growth.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362014000300314

New insight into how thigmomorphogenesis affects Epipremnum aureum plant development
Provedor de dados: 75
Autores: Benedetto,Adalberto Di; Galmarini,Claudio; Tognetti,Jorge.
ABSTRACT Climbing Epipremnum aureum plants develop larger leaves than unsupported, hanging plants. This effect may be regarded, in part, as a thigmomorphogenic response, but gravimorphogenetic effect may also be involved, since polar auxin transport is known to be negatively affected in plants with horizontal or hanging stems, which may result in an altered hormone balance at the whole plant level. The present work was aimed at studying how exogenous auxins and cytokinins may influence growth of E. aureum rooted cuttings under different training systems. Rooted cuttings of E. aureum were cultivated either climbing on an upright wooden board or creeping on the glasshouse bench or hanging from a basket. All leaves of each plant were sprayed to run-off at...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Auxin; Citokinin; Foliage plants; Gravitropism; Leaf growth; Leaf anatomy; Photosynthesis.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362018000300330

Photosynthetic characteristics of phytoplankton in the western Black Sea during the autumn bloom.
Provedor de dados: 13
Autores: Finenko, Z. Z.; Churilova, T. Ya.; Parkhomenko, A. V.; Tugrul, S.
In the autumn of 2005 photosynthetic characteristics of phytoplankton were studied along transects from a coast to deep-waters in the western and southern Black Sea. Efficiency of photosynthesis (αB) varied from 0.012 to 0.068 mg C (mg Chl)-1h-1(μE m-2 s-1)-1. Light – saturated rate of chlorophyll a-normalized photosynthesis (P) ranged from 5 mg C (mg Chl)-1 h-1 in the deep-waters to 12 mg C (mg Chl)-1 h-1 in the shelf waters. In the shelf area P and αB varied by a factor of 3. Variability of these parameters was as lower as that of the chlorophyll concentration. The mean αB and P values at the shelf were higher than those of the deep-water region. The phodoadaptive strategy of phytoplankton was characterized by increasing of αB at lower light levels....
Tipo: Journal Contribution
Palavras-chave: Phytoplankton; Photosynthesis; Light; Primary production; Black Sea; Фитопланктон; Фотосинтез; Свет; Первичная продукция; Чёрное море; Фітопланктон; Світло; Первинна продукція; Чорне море.
Ano: 2008
URL: http://repository.ibss.org.ua/dspace/handle/99011/834

Defasagem entre as produtividades real e potencial do algodoeiro herbáceo: limitações morfológicas, fisiológicas e ambientais.
Provedor de dados: 14
Autores: BELTRÃO, N. E. de M.; AZEVEDO, D. M. P. de.
Fatores limitantes relacionados com a morfologia, a organografia e arquiteture do algodoeiro herbaceo; fatores limitantes relacionados com -a fisiologia e a bioquimica da planta do algodoeiro herbaceo; fatores limitantes relacionados com as condicoes do ambiente; consideracoes holoticas envolvendo fatores da planta e do ambiente.
Tipo: Livro técnico (INFOTECA-E)
Palavras-chave: Herbaceo; Taxas de Crescimento; Cultura; Fotorrespiracao; Trofofilos; Dossel; Balanco; Assimilado; Limitacao incontrolavel; Desenvolvimento; Brasil; Paraiba; Annual cotton; Production; Growth rate; Reespiration; Assimilation; Crop; Levll; Not controllable; Limitation; Growth; Deelopment.; Algodão; Bioquímica; Crescimento; Fotossíntese; Fisiologia Vegetal; Gossypium Hirsutum; Metabolismo; Respiração.; Produção; Biochemistry; Canopy; Leaves; Physiology.; Photosynthesis; Photorespiration; Metabolism.
Ano: 1993
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/264934

Calibração do medidor de clorofila Minolta SPAD-502 para uso na cultura do milho.
Provedor de dados: 14
Autores: ZOTARELLI, L.; CARDOSO, E. G.; PICCININ, J. L.; URQUIAGA, S.; BODDEY, R. M.; TORRES, E.; ALVES, B. J. R.
bitstream/CNPAB-2010/28067/1/cot055.pdf
Tipo: Comunicado Técnico (INFOTECA-E)
Palavras-chave: Calibração; Maize.; Clorofila; Fotossíntese; Medição; Milho; Pigmento.; Calibration; Pigments.; Photosynthesis.
Ano: 2002
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/624249

Investigations on tree species suitable for the recultivation of degraded land areas in Central Amazonia.
Provedor de dados: 14
Autores: SHIFT PROJECT ENV 42-2.
In cooperation with the Embrapa Amazonia Ocidental in Manaus (Amazonas, Brasil) and three German projects (ENV 23, ENV 45, ENV 52), in the year 2000 we especially investigated (1) photosynthesis and carbohydrate allocation and (2) the plant-water relationships of the selected tree species. Special emphasis was given to the three species of the family Meliaceae. Comparative experiments have been done for monoculture, polycultures, enrichment cultures, and primary forests.
Tipo: Outras publicações técnicas (INFOTECA-E)
Palavras-chave: Recuperaco do solo; Agrofloresta; Especie florestal; Fotossinte; Brasil; Amazonas; Tropical rain forest; Reclamation; Sustainability; Species; Plant water relations; Andiroba; Árvore Florestal; Carapa Guianensis; Carboidrato; Cedrela Odorata; Cedro; Cultivo Multiplo; Desenvolvimento Sustentável; Deterioração do Solo; Floresta Tropical Úmida; Mogno; Relação Água-Planta; Swietenia Macrophylla; Uso da Terra; Agroforestry; Carbohydrates; Environmental degradation; Forest trees; Land use; Multiple cropping; Photosynthesis.
Ano: 2001
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/670721

Fluxo diurno de CO2 solo-planta-atmosfera em um campo úmido do cerrado.
Provedor de dados: 14
Autores: MEIRELLES, M. L.; FRANCO, A. C.; FERREIRA, E. A. B.; RANDOW, C. V.
O objetivo deste estudo foi relacionar a altura do lençol freático com os fluxos diurnos de CO2 em um campo limpo úmido (Brasília, DF). Foram monitorados a altura da lâmina do lençol freático; a assimilação de CO2 pelo processo fotossintético de duas gramíneas que representavam 50% da cobertura vegetal; a quantificação do fluxo de CO2 do solo por um equipamento acoplado a câmara de solo; e os fluxos de CO2 atmosférico pelo método micrometeorológico de covariância de vórtices turbulentos. A lâmina de água em 2005 atingiu profundidade de 80 cm e, em 2006, esteve próxima à superfície durante todo o ano, cujas variações não exerceram um efeito na capacidade fotossintética de Axonopus comans, entretanto foram medidos valores menores em Andropogon virgatus,...
Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E)
Palavras-chave: Área úmida; Luminosidade; Wetland; Savanna.; Carbono; Cerrado; Fotossíntese; Lençol Freático; Solo.; Carbon; Groundwater; Photosynthesis; Soil.
Ano: 2010
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/894343

Aspectos biofísicos de cupuaçuzeiro em viveiro.
Provedor de dados: 14
Autores: FIGUEIRÊDO, F. J. C.; ROCHA NETO, O. G. da; CARVALHO, C. J. R. de.
bitstream/item/34425/1/ORIENTAL-BP9.pdf
Tipo: Séries anteriores (INFOTECA-E)
Palavras-chave: Transpiracao; Condutancia estomatica; Resistencia estomatica; Brasil.; Cupuaçu; Fotossíntese; Fruta; Fisiologia Vegetal; Theobroma Grandiflorum.; Amazonia; Fruits; Photosynthesis; Plant physiology.
Ano: 1999
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/377392

Effects of blue light on the biochemical composition and photosynthetic activity of Isochrysis sp. (T-iso)
Provedor de dados: 5
Autores: Marchetti, Julie; Bougaran, Gael; Jauffrais, Thierry; Lefebvre, Sebastien; Rouxel, Catherine; Saint-jean, Bruno; Lukomska, Ewa; Robert, Rene; Cadoret, Jean-paul.
In aquaculture, particularly in bivalve hatcheries, the biochemical composition of algal diets has a strong influence on larval and post-larval development. Biochemical composition is known to be related to culture conditions, among which light represents a major source of variation. The effects of blue light on biochemical composition and photosynthetic rate of Isochrysis sp. (T-iso) CCAP 927/14 were assessed in chemostat at a single irradiance (300 μmol photons m−2 s−1) and compared with white light. Two different dilution (renewal) rates were also tested: 0.7 and 0.2 d−1. Relative carbohydrate content was lower under blue light than under white light at both dilution rates, whereas chlorophyll a and photosynthesis activity were higher. In contrast,...
Tipo: Text
Palavras-chave: Isochrysis; Blue light; Photosynthesis; Proximate composition; Chemostat.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00085/19599/17237.pdf

Evolutionary Dynamics of Chloroplast Genomes in Low Light: A Case Study of the Endolithic Green Alga Ostreobium quekettii
Provedor de dados: 5
Autores: Marcelino, Vanessa R.; Cremen, Ma Chiela M.; Jackson, Chistopher J.; Larkum, Anthony A. W.; Verbruggen, Heroen.
Some photosynthetic organisms live in extremely low light environments. Light limitation is associated with selective forces as well as reduced exposure to mutagens, and over evolutionary timescales it can leave a footprint on species' genomes. Here, we present the chloroplast genomes of four green algae (Bryopsidales, Ulvophyceae), including the endolithic (limestone-boring) alga Ostreobium quekettii, which is a low light specialist. We use phylogenetic models and comparative genomic tools to investigate whether the chloroplast genome of Ostreobium corresponds to our expectations of how low light would affect genome evolution. Ostreobium has the smallest and most gene-dense chloroplast genome among Ulvophyceae reported to date, matching our expectation...
Tipo: Text
Palavras-chave: Genome streamlining; Photosynthesis; Rates of evolution; Boring algae; Stoichiogenomics.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00659/77094/78418.pdf

How do microalgae perceive light in a high-rate pond? Towards more realistic Lagrangian experiments
Provedor de dados: 5
Autores: Demory, David; Combe, Charlotte; Hartmann, Philipp; Talec, Amelle; Pruvost, Eric; Hamouda, Raouf; Souille, Fabien; Lamarea, Pierre-olivier; Bristeau, Marie-odile; Sainte-marie, Jacques; Rabouille, Sophie; Mairet, Francis; Sciandra, Antoine; Bernard, Olivier.
Hydrodynamics in a high-rate production reactor for microalgae cultivation affects the light history perceived by cells. The interplay between cell movement and medium turbidity leads to a complex light pattern, whose forcing effects on photosynthesis and photoacclimation dynamics are nontrivial. Hydrodynamics of high density algal ponds mixed by a paddle wheel has been studied recently, although the focus has never been on describing its impact on photosynthetic growth efficiency. In this multidisciplinary downscaling study, we first reconstructed single cell trajectories in an open raceway using an original hydrodynamical model offering a powerful discretization of the Navier-Stokes equations tailored to systems with free surfaces. The trajectory of a...
Tipo: Text
Palavras-chave: Photosynthesis; Hydrodynamics; Modelling; Photoacclimation; Dunaliella salina; Non-photochemical quenching.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00445/55692/57352.pdf

Seasonal variations in photosynthetic irradiance response curves of macrophytes from a Mediterranean coastal lagoon
Provedor de dados: 5
Autores: Plus, Martin; Auby, Isabelle; Verlaque, Marc; Levavasseur, Guy.
The main photosynthesis and respiration parameters (dark respiration rate, light saturated production rate, saturation irradiance, photosynthetic efficiency) were measured on a total of 23 macrophytes of the Than lagoon (2 Phanerogams, 5 Chlorophyceae, 10 Rhodophyceae and 6 Phaeophyceae). Those measurements were performed in vitro under controlled conditions, close to the natural ones, and at several seasons. Concomitantly, measurements of pigment concentrations, carbon, phosphorous and nitrogen contents in tissues were performed. Seasonal intra-specific variability of photosynthetic parameters was found very high, enlightening an important acclimatation capacity. The highest photosynthetic capacities were found for Chlorophyceae (e.g. Monostroma obscurum...
Tipo: Text
Palavras-chave: Thau lagoon; Phaeophyceae; Rhodophyceae; Chlorophyceae; Seagrasses; Seasonal variations; Oxygen method; Macrophytes; Light response curve; Photosynthesis.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/publication-465.pdf

Etude du biofilm microalgal des vasières intertidales : dynamique spatio-temporelle à micro-échelle et performances photosynthétiques
Provedor de dados: 5
Autores: Herlory, Olivier.
The microalgal biofilm, which is present on sediment surface, is the primary production unit on bare intertidal mudlfats. In order to improve our understanding of this primary production system, a study was undertaken at microscale to analyse the structural and functional properties of this biofilm. In the first part of this work, a detailed descriptive analysis lead to the characterisation of the spatiotemporal dynamics of the physical structure of the biofilm. It turns out that the biofilm exhibits its own dynamics at the sediment surface (as a discrete compartment in the top 200 µm), but still has a functional relationship with the total available biomass (PCB) distributed within the top 1 cm (linear relationship between the maximum size of the biofilm...
Tipo: Text
Palavras-chave: PAM Fluorometry; Scanning electron microscopy; Photosynthesis; Spatio temporal dynamic; Micro scale; Microphytobenthic biofilm; Intertidal mudflats; Fluorimétrie PAM; Microscopie électronique à balayage; Photosynthèse; Dynamique spatio temporelle; Micro échelle; Biofilm microphytobenthique; Vasière intertidal.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/these-2138.pdf

The use of high rate algal ponds for the treatment of marine effluent from a recirculating fish rearing system
Provedor de dados: 5
Autores: Pagand, Pascal; Blancheton, Jean-paul; Lemoalle, J; Casellas, C.
A high rate algal pond (HRAP) system was used to treat effluent from a recirculating sea water aquaculture system in southern France. Dicentrarchus labrax L. were farmed at a high density, with effluents containing an average of 10 mg L-1 dissolved inorganic nitrogen (DIN) and 1.3 mg L-1 reactive phosphorus (RP). On a yearly basis, the algal pond removed 59% of the dissolved nitrogen and 56% of the phosphorus input, which was converted into 3.3 kg DW m(-2) algae. Green macroalgae were dominant throughout the year and the algal biomass mirrored the seasonal changes in daily irradiance and temperature. This first year study supports the possibility of treating marine aquaculture wastes using HPAPs, although conditions will have to be found to mitigate the...
Tipo: Text
Palavras-chave: Nitrogen; Biofilters; Irradiance; Temperature; Photosynthesis; Growth; Culture; Chlorophyta; Nutrient Removal.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/2000/publication-515.pdf

In situ growth potential of the subtidal part of green tide forming Ulva spp. stocks
Provedor de dados: 5
Autores: Merceron, Michel; Antoine, Virginie; Auby, Isabelle; Morand, P.
Ulva spp., the algae most responsible for green tides in Brittany (France), are found on the foreshore and in the most beachward wave area (MBWA) of many bays during green tide phenomena. These algae have recently been seen drifting at greater depths (reaching -20 m). In view of the significant quantities of algae found at these depths, and the less favorable conditions for algal growth than in the intertidal zone, we attempted to determine if they could grow there. For that, during their maximum growth period (from May to July), algae were picked up at three stations located on the foreshore, in the MBWA and in the subtidal (deep) zones of the Bay of Douarnenez, and their nitrogen, carbon and chlorophyll a+b contents were determined, and their...
Tipo: Text
Palavras-chave: Nutrients; Irradiance; Photosynthesis; Ulva sp.; Algal blooms; Eutrophication.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-3527.pdf

Les chaines alimentaires naturelles et l'aquaculture
Provedor de dados: 5
Autores: Barnabe, G.
Aquaculture sets up manipulation of natural food chains. This paper describes some utilizations of photosynthetic bacteria, phytoplankton and zooplankton taken out sewage ponds, wetlands or neritic waters.
Tipo: Text
Palavras-chave: Bacteria; Photosynthesis; Aquaculture; Ecosystems; Zooplankton; Phytoplankton; Food chains.
Ano: 1983
URL: http://archimer.ifremer.fr/doc/1983/acte-1254.pdf

The Role of Sustained Photoprotective Non-photochemical Quenching in Low Temperature and High Light Acclimation in the Bloom-Forming Arctic Diatom Thalassiosira gravida
Provedor de dados: 5
Autores: Lacour, Thomas; Lariviere, Jade; Ferland, Joannie; Bruyant, Flavienne; Lavaud, Johann; Babin, Marcel.
Thalassiosira gravida is a major Arctic diatom responsible for the under-ice spring bloom. We investigated T. gravida physiological plasticity growing it at two temperatures (0 and 5°C) and under different light intensities typically found in its natural environment. T. gravida showed remarkable thermal- and photo-acclimatory plasticity including: low light saturation parameter for growth (KE) and photosynthesis (EK), low μmax but relatively high Chl a/C, low C/N, and decreasing light-saturated carbon fixation rate (PmC) with increasing growth irradiance. T. gravida also showed remarkable photoprotective features, namely a strong sustained non-photochemical quenching (NPQs, hour kinetics relaxation) supported by a high amount of xanthophyll cycle pigments....
Tipo: Text
Palavras-chave: Arctic diatom; Photosynthesis; Sustained NPQ; Irradiance; Temperature.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00462/57387/59468.pdf

Allelochemicals of Alexandrium minutum: Kinetics of membrane disruption and photosynthesis inhibition in a co-occurring diatom
Provedor de dados: 5
Autores: Long, Marc; Peltekis, Alexandra; González-fernández, Carmen; Hégaret, Helene; Bailleul, Benjamin.
Allelopathy is an efficient strategy by which some microalgae can outcompete other species. Allelochemicals from the toxic dinoflagellate Alexandrium minutum have deleterious effects on diatoms, inhibiting metabolism and photosynthesis and therefore give a competitive advantage to the dinoflagellate. The precise mechanisms of allelochemical interactions and the molecular target of allelochemicals remain however unknown. To understand the mechanisms, the short-term effects of A. minutum allelochemicals on the physiology of the diatom Chaetoceros muelleri were investigated. The effects of a culture filtrate were measured on the diatom cytoplasmic membrane integrity (polarity and permeability) using flow-cytometry and on the photosynthetic performance using...
Tipo: Text
Palavras-chave: Allelochemicals; Allelopathy; Alexandrium minutum; Chaetoceros muelleri; Photosynthesis; Membrane.
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00680/79191/81688.pdf

Role des bacteries phototrophes anoxygeniques dans une partie stratifiee d'une lagune tropicale (Lagune Ebrie, Cote d'Ivoire)
Provedor de dados: 5
Autores: Caumette, P.
In the deepest parts of the estuarine region of Ebrie Lagoon (Abidjan Africa, (5 degree N, 4 degree W) stratified conditions have been observed during the rainy season (May to Nov.), owing to salinity differences between oxic and anoxic layers. At the interface, 3-4 m depth, phototrophic bacteria (Chromatium, Chlorobium and Pelodictyon ) developed, forming a brown layer due to their different pigments. Their production has been estimated at 41% of the total photosynthetic production during high stratification (Sep. 1981) and their biomass was used by the copepod population for 40 to 60% of its diet. During the dry season, the water column became homogeneous and oxygen was detected to 6m depth. The brown layer of phototrophic bacteria disappeared, as well...
Tipo: Text
Palavras-chave: Chlorobium; Chromatium; Primary production; Photosynthesis; Estuaries; Seasonal variations; Plankton; Stratification; Vertical distribution; Bacteria; Coastal lagoons; Trophic relationships; Biomass.
Ano: 1984
URL: http://archimer.ifremer.fr/doc/1984/acte-957.pdf

Coping with branch excision when measuring leaf net photosynthetic rates in a lowland tropical forest
Provedor de dados: 5
Autores: Verryckt, Lore T.; Van Langenhove, Leandro; Ciais, Philippe; Courtois, Elodie A.; Vicca, Sara; Peñuelas, Josep; Stahl, Clément; Coste, Sabrina; Ellsworth, David S.; Posada, Juan M.; Obersteiner, Michael; Chave, Jérôme; Janssens, Ivan A.
Measuring leaf gas exchange from canopy leaves is fundamental for our understanding of photosynthesis and for a realistic representation of carbon uptake in vegetation models. Since canopy leaves are often difficult to reach, especially in tropical forests with emergent trees up to 60 m at remote places, canopy access techniques such as canopy cranes or towers have facilitated photosynthetic measurements. These structures are expensive and therefore not very common. As an alternative, branches are often cut to enable leaf gas exchange measurements. The effect of branch excision on leaf gas exchange rates should be minimized and quantified to evaluate possible bias. We compared light‐saturated leaf net photosynthetic rates measured on excised and intact...
Tipo: Text
Palavras-chave: Branch cutting; Canopy physiology; French Guiana; Gas exchange; Photosynthesis; Rainforest; Stomatal conductance.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00613/72466/71949.pdf

Transient initial phase in continuous culture of Isochrysis galbana affinis Tahiti
Provedor de dados: 5
Autores: Bougaran, Gael; Le Dean, Loic; Lukomska, Ewa; Kaas, Raymond; Baron, Regis.
Starting microalgae continuous culture generally includes a preliminary batch culture to obtain sufficient cell density. It is possible to apply continuous regime from the beginning of the culture (IC mode) rather than to begin by an initial batch (IB mode). It is our purpose to check that both initial modes lead to identical steady-state cell characteristics. The microalga Isochrysis galbana affinis Tahiti was used for this comparative study. With an initial cell density of 5 x 10(5) cell ml(-1) and a dilution rate of about 1.0 d(-1), both IB and IC modes led to identical cell density once steady-state is reached between 6 and 8 d after inoculation in the two cases. Cell concentration of chlorophyll a and pheopigment a were found to be similar for IB and...
Tipo: Text
Palavras-chave: Isochrysis; Cell quota; Photosynthesis; Steady state; Continuous culture.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/publication-597.pdf

Effects of copper and butyltin compounds on the growth, photosynthetic activity and toxin production of two HAB dinoflagellates : the planktonic Alexandrium catenella and the benthic Ostreopsis cf. ovata
Provedor de dados: 5
Autores: Couet, Douglas; Pringault, Olivier; Bancon-montigny, Chrystelle; Briant, Nicolas; Poulichet, Francoise Elbaz; Delpoux, Sophie; Yahia, Ons Kefi-daly; Hela, Bengharbia; Charaf, M'Rabet; Herve, Fabienne; Rovillon, Georges-augustin; Amzil, Zouher; Laabir, Mohamed.
Controlled laboratory experiments were conducted to test the effects of copper (Cu2+) and butyltins (BuT) on the growth, photosynthetic activity and toxin content of two HABs (Harmful Algal Blooms) dinoflagellates, the planktonic Alexandrium catenella and the benthic Ostreopsis cf. ovata. Microalgae were exposed to increasing concentrations of Cu2+ (10−4 to 31 nM) or BuT (0.084 to 84 nM) for seven days. When considering the growth, EC50 values were 0.16 (±0.09) nM and 0.03 (±0.02) nM of Cu2+ for A. catenella and O. cf. ovata, respectively. Regarding BuT, EC50 was 14.2 (±6) nM for O. cf. ovata, while A. catenella growth inhibition appeared at BuT concentrations ≥27 nM. Photosynthetic activity of the studied dinoflagellates decreased with increasing Cu and...
Tipo: Text
Palavras-chave: Alexandrium catenella; Ostreopsis cf. ovata; Cu; Butyltin; Photosynthesis; Toxins.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00418/52970/53896.pdf

Response of CO2-starved diatom Phaeodactylum tricornutum to light intensity transition
Provedor de dados: 5
Autores: Heydarizadeh, Parisa; Boureba, Wafaa; Zahedi, Morteza; Huang, Bing; Moreau, Brigitte; Lukomska, Ewa; Couzinet-mossion, Aurelie; Wielgosz-collin, Gaetane; Martin-jezequel, Veronique; Bougaran, Gael; Marchand, Justine; Schoefs, Benoit.
In this study, we investigated the responses of Phaeodactylum tricornutum cells acclimated to 300 mu mol m(-2) s(-1) photon flux density to an increase (1000 mmol m(-2) s(-1)) or decrease (30 mmol m(-2)s(-1)) in photon flux densities. The light shift occurred abruptly after 5 days of growth and the acclimation to new conditions was followed during the next 6 days at the physiological and molecular levels. The molecular data reflect a rearrangement of carbon metabolism towards the production of phosphoenolpyruvic acid (PEP) and/or pyruvate. These intermediates were used differently by the cell as a function of the photon flux density: under low light, photosynthesis was depressed while respiration was increased. Under high light, lipids and proteins...
Tipo: Text
Palavras-chave: Phaeodactylum tricornutum; Carbon metabolism; Light regulation; Photosynthesis; Chlorophyll fluorescence; Pyruvate hub.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00395/50620/52341.pdf

Decoupling light harvesting, electron transport and carbon fixation during prolonged darkness supports rapid recovery upon re-illumination in the Arctic diatom Chaetoceros neogracilis
Provedor de dados: 5
Autores: Lacour, Thomas; Morin, Philippe-israël; Sciandra, Théo; Donaher, Natalie; Campbell, Douglas A.; Ferland, Joannie; Babin, Marcel.
During winter in the Arctic marine ecosystem, diatoms have to survive long periods of darkness caused by low sun elevations and the presence of sea ice covered by snow. To better understand how diatoms survive in the dark, we subjected cultures of the Arctic diatom Chaetoceros neogracilis to a prolonged period of darkness (1 month) and to light resupply. Chaetoceros neogracilis was not able to grow in the dark but cell biovolume remained constant after 1 month in darkness. Rapid resumption of photosynthesis and growth recovery was also found when the cells were transferred back to light at four different light levels ranging from 5 to 154 µmol photon m−2 s−1. This demonstrates the remarkable ability of this species to re-initiate growth over a wide range...
Tipo: Text
Palavras-chave: Arctic microalgae; Polar night; Diatom; Darkness; Photosynthesis; Growth rate; Temperature.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00499/61066/64597.pdf

Combined effects of global climate change and nutrient enrichment on the physiology of three temperate maerl species
Provedor de dados: 5
Autores: Qui-minet, Zujaila Nohemy; Coudret, Jérôme; Davoult, Dominique; Grall, Jacques; Mendez‐sandin, Miguel; Cariou, Thierry; Martin, Sophie.
Made up of calcareous coralline algae, maerl beds play a major role as ecosystem engineers in coastal areas throughout the world. They undergo strong anthropogenic pressures, which may threaten their survival. The aim of this study was to gain insight into the future of maerl beds in the context of global and local changes. We examined the effects of rising temperatures (+3°C) and ocean acidification (−0.3 pH units) according to temperature and pH projections (i.e., the RCP 8.5 scenario), and nutrient (N and P) availability on three temperate maerl species (Lithothamnion corallioides, Phymatolithon calcareum, and Lithophyllum incrustans) in the laboratory in winter and summer conditions. Physiological rates of primary production, respiration, and...
Tipo: Text
Palavras-chave: Calcification; Maerl; Nitrate; Ocean acidification; Ocean warming; Phosphate; Photosynthesis; Respiration.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00595/70722/68955.pdf

Effect of Bentazon on Growth and Physiological Responses of Marine Diatom: Chaetoceros gracilis
Provedor de dados: 5
Autores: Hourmant, Annick; Amara, Anis; Pouline, Patrick; Durand, Gael; Arzul, Genevieve; Quiniou, Francoise.
The herbicide bentazon (CASRN 25057-89-0) is extensively used in agriculture in Brittany (France) to replace atrazine. Bentazon is not readily adsorbed by soil and therefore it enters adjacent freshwater ecosystems, making its way to estuarine and marine waters areas. Information regarding its effects on marine ecosystems is scarce. Phytotoxicity assessments were conducted in the laboratory on the common diatom Chaetoceros gracilis using both the active ingredient and its formulated product (Basamais). The 3 day EC50 Using cell counts were, respectively, 150 mg/L and 60 mu g/L for bentazon active ingredient and for bentazon-formulated while cellular volume was increased. Although bentazon is known as a photosystem II inhibitor, it produced an increase of...
Tipo: Text
Palavras-chave: Photosynthesis; Marine diatom; Growth; Chlorophylls; Chaetoceros gracilis; Carotenoids; Bentazon; ATP.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6637.pdf

Toxicity of binary mixtures of pesticides to the marine microalgae Tisochrysis lutea and Skeletonema marinoi: Substance interactions and physiological impacts
Provedor de dados: 5
Autores: Dupraz, Valentin; Ménard, Dominique; Akcha, Farida; Budzinski, Hélène; Stachowski-haberkorn, Sabine.
This study screened binary mixtures of pesticides for potential synergistic interaction effects on growth of the marine microalgae Tisochrysis lutea and Skeletonema marinoi. It also examined the single and combined effects of three of the most toxic substances on microalgal physiology. Single substances were first tested on each microalgal species to determine their respective EC50 and concentration-response relationships. The toxicity of six and seven binary mixtures was then evaluated in microplate experiments on the growth of T. lutea and S. marinoi, respectively, using two mixture modelling approaches: isobolograms and the MIXTOX tool, based on Concentration Addition (CA) or Independent Action (IA) models. Significant cases of antagonism (for both...
Tipo: Text
Palavras-chave: ROS; Photosynthesis; Lipids; Synergy; Isoproturon; Metazachlor.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00488/59928/63131.pdf

Reduction of photosynthesis before midday depression occurred: leaf photosynthesis of Fagus crenata in a temperate forest in relation to canopy position and a number of days after rainfall
Provedor de dados: 19
Autores: Koyama, Kohei; Kikuzawa, Kihachiro.
We investigated an effect of canopy position and a number of days after rainfall on reduction of photosynthetic rate in a Fagus crenata forest in summer 2008, during days when midday depression was not apparent. We compared in situ photosynthetic rate and photosynthetic rate that was calculated by photosynthetic light response curves measured in the morning. The ratio, in situ photosynthesis divided by the curve-estimated value, declined towards the end of each day for the upper leaves, but not for the lower leaves. Total photosynthesis was reduced only for the upper leaves by 12% during 5 days after the rainfall.
Palavras-chave: Photosynthesis; Stomatal conductance; Net primary production; Temperate forest; Fagus crenata Blume.
Ano: 2011
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4483

Estimaciones satelitales de clorofila y los frentes oceánicos del Atlántico Sudoccidental
Provedor de dados: 20
Autores: Romero, S.I.
Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales (Argentina)
Tipo: Theses and Dissertations
Palavras-chave: Chlorophylls; Continental shelves; Shelf fronts; Estuarine front; Shelf edge fronts; Variability; Phytoplankton; Photosynthesis; Satellite sensing; Phytoplankton; Chlorophylls; Continental shelves; Photosynthesis; Http://aims.fao.org/aos/agrovoc/c_13344; Http://aims.fao.org/aos/agrovoc/c_1577; Http://aims.fao.org/aos/agrovoc/c_32413; Http://aims.fao.org/aos/agrovoc/c_5812.
Ano: 2008
URL: http://hdl.handle.net/1834/2827

Efectos de la radiación solar sobre el fitoplancton de aguas antárticas y subantárticas
Provedor de dados: 20
Autores: Hernando, M.P.
The increments in the ultraviolet radiation B (RUVB, 280-320 nm) resultants of the destruction of the ozone layer affect diverse echo-physiologic aspects of the marine phytoplankton. On this study were compared the responses of phytoplankton from an ambient Sub-Antarctic (Channel Beagle, 54º 52´S, 68º 18´W) and another Antarctic (Potter Cove, 62º 14´S, 58º 38´W) to the ultraviolet radiation (RUV). The decrease of the photosynthesis on short term (hours) was observed in both places, however inhibition thresholds were present. In the Beagle Channel, these were for RUVB and ultraviolet radiation A (RUVA, 320-400 nm), respectively, 0,2 and 6,2 Wm-2 for communities with more than 70% diatoms and 0,45 and 14,2 Wm-2, respectively, for communities with more than...
Tipo: Theses and Dissertations
Palavras-chave: Phytoplankton; Photosynthesis; Ultraviolet radiation; Vertical mixing; Taxonomy; Phytoplankton; Taxonomy; Photosynthesis; Ultraviolet radiation; Http://aims.fao.org/aos/agrovoc/c_13344; Http://aims.fao.org/aos/agrovoc/c_7631; Http://aims.fao.org/aos/agrovoc/c_5812; Http://aims.fao.org/aos/agrovoc/c_8046.
Ano: 2008
URL: http://hdl.handle.net/1834/2868

Leaf gas exchange differences between males and females of yerba-mate
Provedor de dados: 190
Autores: Rakocevic, Miroslava; Medrado, Moacir José Sales; Lavoranti, Osmir José.
A preliminary study was developed on leaf gas exchange properties of males and females in yerbamate (Ilex paraguariensis St. Hil.), planted in open growth conditions. The photosynthesic photon flux density (PPFD) on leaf level, stomatal conductance (gs), net photosynthesis (A), transpiration (E), and leaf temperature (Tl) was measured during the biennial production period: in the summer during the fruit ripening when there is a pause in its growth (January, February), spring  sprouting (November) and autumn sprouting (March, Jun). The measurements have been taken in different tree crown positions (inside, exterior and tips). First indications of sex physiological  dimorphism in yerba-mate have been shown.  Conductance was superior on female plants, with...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Light; Photosynthesis; Stomatal conductance; Temperature; Transpiration Condutância estomática; Fotossíntese; Luz; Temperatura; Transpiração.
Ano: 2010
URL: http://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/127

Ecophysiological and Productive Properties as Tool for Breeding of Maté (Ilex paraguariensis St. Hil.)
Provedor de dados: 190
Autores: Rakocevic, Miroslava; Sturion, José Alfredo; Medrado, Moacir José Sales; Lavoranti, Osmir José; Mosele, Sérgio Henrique; Valduga, Alice Tereza.
The aims of this study were to estimate the genetic parameters for 59 half-sib progenies of maté under runing for formation, and to evaluate the ecophysiological properties for four progenies (P15, P18, P41 e  47) and two controls (P61 and P62), components of one maté breeding experiment combining  rovenances and progenies, established in Erechim, RS. The ecophysiological properties (stomatal  onductance (gs) - mol m-2s-1, net photosynthesis (A) - μmol CO2 m-2s-1, and transpiration (E) -mmol H2O  - s-1) were measured during one year in five epochs (from September 2002 to August 2003). The variance  omponents, genetic and phenotypic parameters and genetic values (for data of foliar mass collected in  runing of formation) were obtained using a...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Genetic value; Heritability; Photosynthesis; Stomatal conductance; Transpiration. Condutância estomática; Fotossíntese; Herdabilidade; Transpiração; Valor genético.
Ano: 2011
URL: http://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/229

Quality of yerba-mate leaves originating from male and female plants
Provedor de dados: 190
Autores: Rakocevic, Miroslava; Medrado, Moacir José Sales; Lavoranti, Osmir José; Valduga, Alice Teresa.
The aim of this study was to assess the taste of beverage prepared from yerba-mate (Ilex paraguariensis) leaves, originated from male and female plants, by taking into account leaf gas exchange and the content of macro-and-trace-elements. Ecophysiological, chemical and sensorial properties were evaluated in one of the sprouting phases and in two fruit ripening phases. Male and female plants did not differ in fresh and dry matter production per plant, nor in the content of micro- and trace elements. However, female plants showed higher leaf net photosynthesis (A) and stomatal conductance (gs) than male plants. The beverage prepared with male plant leaves was less bitter than that prepared with female plant leaves, especially when leaves from the branch tips...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Macronutrients; Photosynthesis; Productivity; Stomatal conductance; Bitterness; Trace elements Amargo; Condutância estomática; Fotossíntese; Macro-elementos; Micro-elementos; Produtividade.
Ano: 2010
URL: http://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/131

Low temperature impact on photosynthetic parameters of coffee genotypes
Provedor de dados: 86
Autores: Partelli,Fábio Luiz; Vieira,Henrique Duarte; Viana,Alexandre Pio; Batista-Santos,Paula; Rodrigues,Ana Paula; Leitão,António Eduardo; Ramalho,José Cochicho.
The objective of this work was to evaluate photoprotective mechanisms related to low positive temperatures in Coffea canephora (Conilon clones 02 and 153) and C. arabica ('Catucaí' IPR 102) genotypes, involved in cold temperature tolerance. To accomplish this, one-year-old plants were successively submitted to: temperature decrease of 0.5ºC day-1, from 25/20ºC to 13/8ºC; a three-day chilling cycle at 13/4ºC; and a recovery period of 14 days (25/20ºC). During the experiment, leaf gas exchange, chlorophyll a fluorescence and leaf photosynthetic pigment content were evaluated. Total activity of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and ribulose-5-phosphate kinase (Ru5PK) were quantified to measure the activity of photosynthesis key...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Coffea; Carotenoids; Photoprotection; Photosynthesis; Rubisco.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2009001100006

Physiological responses of two tropical weeds to shade: II. Leaf gas exchange and nitrogen content
Provedor de dados: 86
Autores: Dias-Filho,Moacyr Bernardino.
Ipomoea asarifolia (Desr.) Roem. &amp;amp; Schultz (Convolvulaceae) and Stachytarpheta cayennensis (Rich) Vahl. (Verbenaceae), two weeds found in pastures and crop areas in the Brazilian Amazonia, Brazil, were grown in controlled environment cabinets under high (800-1000 µmol m-² s-¹) and low (200-350 µmol m-² s-¹) light regimes during a 40-day period. The objective was to determine the effect of shade on photosynthetic features and leaf nitrogen content of I. asarifolia and S. cayennensis. High-irradiance grown I. asarifolia leaves had significantly higher dark respiration and light saturated rates of photosynthesis than low-irradiance leaves. No significant differences for these traits, between treatments, were observed in S. cayennensis. Low-irradiance...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Leaf nitrogen; Amazonia; Ipomoea asarifolia; Stachytarpheta cayennensis.
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X1999000600005

Physiological and N2-fixation-related traits for tolerance to drought in soybean progenies
Provedor de dados: 86
Autores: Cerezini,Paula; Kuwano,Biana Harumi; Neiverth,Walkyria; Grunvald,Anna Karolina; Pípolo,Antonio Eduardo; Hungria,Mariangela; Nogueira,Marco Antonio.
Abstract: The objective of this work was to evaluate six soybean (Glycine max) genotypes for physiological traits and biological nitrogen fixation in drought conditions, and their capacity for recovery after rewetting, based on yield components. The genotypes evaluated in a greenhouse were the following: 'BRS 317', susceptible to drought; R01-581F and R02-1325, which show biological nitrogen fixation tolerant to drought; and the BRB14-207525, BRB14-207526, BRB14-207527 breed lines resulting from crossings between commercial genotypes and PI 471938, which shows a slow-wilting phenotype under drought. Drought conditions were applied to the genotypes at the full-flowering stage (R2) for ten days, whereas control plants were kept well-watered. Photosynthetic...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bradyrhizobium; Glutamine synthetase; Photosynthesis; Rewetting; Ureides.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2019000103302

Physiological and morphological responces of Brachiaria spp. to flooding
Provedor de dados: 86
Autores: DIAS-FILHO,MOACYR BERNARDINO; CARVALHO,CLÁUDIO JOSÉ REIS DE.
The physiological and morphological responses of the forage grasses Brachiaria brizantha cv. Marandu, B. decumbens and B. humidicola were compared for plants grown in pots under flooding and well-drained conditions for 14 days. Flooding reduced specific leaf area and biomass allocation to roots in all species and enhanced leaf senescence in B. brizantha and B. decumbens. Relative growth rate was reduced by flooding in B. brizantha and B. decumbens, but not in B. humidicola.Leaf elongation rate was unaffected by flooding in B. decumbens and B. humidicola, but declined in B. brizantha since the first day of flooding. Net photosynthesis and leaf chlorophyll content were reduced by flooding in B. brizantha; however, no flooding effect could be detected in the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Brachiaria brizantha; Brachiaria decumbens; Brachiaria humidicola; Leaf area; Chlorophyll; Photosynthesis; Biomass; Growth rate.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2000001000006

Physiological and anatomical characteristics of leaves of two clones of guarana
Provedor de dados: 86
Autores: Gonçalves,José Francisco de Carvalho; Santos Júnior,Ulysses Moreira dos; Silva,José Ferreira da; Arruda,Murilo Rodrigues de; Bonates,Luiz Carlos de Matos; Fernandes,Andreia Varmes.
The objective of this work was to analyze gas exchange, photosynthetic characteristics, photochemical efficiency of photosystem II and anatomical characteristics of young plant leaves of two guarana (Paullinia cupana) clones (BRS-CG372RC and BRS-CG611RL) growing under open field. The variables of gas exchange and fluorescence of chlorophyll a were evaluated in mature leaves. The values of photosynthesis and transpiration found for BRS-CG372RC were 27% greater and 80% lesser than values found for BRS-CG611RL, respectively. The values of stomatal conductance found for the clones BRS-CG372RC and BRS-CG611RL were in the order of 224 and 614 mmol mm-2 s-1, respectively. The values of photorespiration, rate of carboxylation and rate electron transport were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Paullinia cupana; Photosynthesis; Photochemical efficiency of photosystem II; Electron transport rate; Water use efficiency; Stomatal anatomy.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2006000300004

CO2-response function of radiation use efficiency in rice for climate change scenarios
Provedor de dados: 86
Autores: Streck,Nereu Augusto; Rosa,Hamilton Telles; Walter,Lidiane Cristine; Silva,Michel Rocha da; Uhlmann,Lilian Osmari.
The objective of this work was to evaluate a generalized response function to the atmospheric CO2 concentration [f(CO2)] by the radiation use efficiency (RUE) in rice. Experimental data on RUE at different CO2 concentrations were collected from rice trials performed in several locations around the world. RUE data were then normalized, so that all RUE at current CO2 concentration were equal to 1. The response function was obtained by fitting normalized RUE versus CO2 concentration to a Morgan-Mercer-Flodin (MMF) function, and by using Marquardt's method to estimate the model coefficients. Goodness of fit was measured by the standard deviation of the estimated coefficients, the coefficient of determination (R²), and the root mean square error (RMSE). The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oryza sativa; Global warming; Modeling; Photosynthesis.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2012000700001

Sensitivity of yellow passion fruit to ultraviolet-B radiation
Provedor de dados: 86
Autores: Cechin,Inês; Rocha,Valéria de Jesus; Fumis,Terezinha de Fátima.
The objective of this work was to evaluate the effects of UV-B radiation on the vegetative growth and on the gas exchange characteristics of passion fruit plants (Passiflora edulis) grown in greenhouse. The average unweighted UV-B radiation near the apex of the plants was 8 W m-2 for the UV-B treatment (high UV-B), and 0.8 W m-2 for the control plants (low UV-B). Plants were irradiated with UV-B for 7 hours per day, centered on solar noon, during 16 days. High UV-B radiation resulted in lower shoot dry matter accumulation per plant. The content of UV-B absorbing compounds and anthocyanins was increased in the plants exposed to high UV-B radiation, when compared with the control. UV-B radiation did not affect stomatal conductance or transpiration rate, but...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Passiflora edulis; Anthocyanins; Growth; Phenolic compounds; Photosynthesis.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2012001000002

Tolerance to flooding in five Brachiaria brizantha accessions
Provedor de dados: 86
Autores: Dias-Filho,Moacyr Bernardino.
Some physiological and morphological responses of five Brachiaria brizantha accessions (BRA000591 cultivar Marandu, BRA003441, BRA002844, BRA004308 and BRA004391) were compared for plants grown in pots under flooding and well-drained conditions for 14 days. Flooding caused a significant reduction in leaf dry mass production in all accessions, but, for root biomass, no differences between treatments could be detected in BRA003441 and BRA004391. No adventitious root production was observed in flooded BRA003441; all other accessions produced adventitious roots when flooded. Relative growth rate was reduced by flooding only in BRA000591 and BRA004308. Leaf elongation rate was reduced by flooding in all accessions, however, more severely in BRA003441. Net...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adventitious roots; Photosynthesis; Forage grasses; Biomass allocation; Growth rate.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2002000400003

Environmental effects on photosynthetic capacity of bean genotypes
Provedor de dados: 86
Autores: Ribeiro,Rafael Vasconcelos; Santos,Mauro Guida dos; Souza,Gustavo Maia; Machado,Eduardo Caruso; Oliveira,Ricardo Ferraz de; Angelocci,Luiz Roberto; Pimentel,Carlos.
Photosynthetic responses to daily environmental changes were studied in bean (Phaseolus vulgaris L.) genotypes 'Carioca', 'Ouro Negro', and Guarumbé. Light response curves of CO2 assimilation and stomatal conductance (g s) were also evaluated under controlled (optimum) environmental condition. Under this condition, CO2 assimilation of 'Carioca' was not saturated at 2,000 µmol m-2 s-1, whereas Guarumbé and 'Ouro Negro' exhibited different levels of light saturation. All genotypes showed dynamic photoinhibition and reversible increase in the minimum chlorophyll fluorescence yield under natural condition, as well as lower photosynthetic capacity when compared with optimum environmental condition. Since differences in g s were not observed between natural and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Phaseolus vulgaris; Chlorophyll fluorescence; Gas exchange; Photosynthesis.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2004000700001

Leaf photosynthetic characteristics in eight shaded Malaysian filmy ferns
Provedor de dados: 85
Autores: Nurul Hafiza,MR; Yong,KT; Osman,N; Nasrulhaq-Boyce,A.
The photosynthetic characteristics of eight Malaysian Hymenophyllaceae filmy ferns from shady habitats were investigated in this study. Chlorophyll content was highest in Trichomanes meifolium, followed by Cephalomanes obscurum, Hymenophyllum serrulatum, H. denticulatum, H. javanicum, H. acanthoides, H. exsertum and H. blandum, with values ranging from 3.3 to 8.6 mg/g fresh weight. Soluble protein content was remarkably high in H. serrulatum, with values of 53 ± 3.50 mg/g, followed by H. denticulatum, H. acanthoides, T. meifolium and the other species. Protein to chlorophyll ratios in the filmy ferns were low as expected, except for in H. serrulatum, H. acanthoides and H. denticulatum. Chloroplast number and size ranged between 34 to 138 per cell profile,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Plant science; Photosynthesis; Filmy ferns; Hymenophyllaceae; Shaded habitats.
Ano: 2014
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1851-56572014000200018

Photosynthesis and water use efficiency of the association between Larrea tridentata (DC) Cov. and Muhlenbergia porteri Scribn
Provedor de dados: 85
Autores: Castellanos-Pérez,E; de Soyza,Ag; Donart,Gb.
The study was conducted in the Chihuahuan Desert Rangeland Research Center, 32 km north of Las Cruces, NM, USA. Physiological responses of the shrub Larrea tridentata (DC) Cov. and the perennial grass Muhlenbergia porteri Scribn were determined from the summer 1997 to the winter 1998-99 when they grew together. In the summer 1997 Larrea tridentata competed for water with M. porteri, as shrubs growing alone showed higher integrated photosynthesis than shrubs in competi-tion with M. porteri following a heavy rainfall event. Larrea tridentata had lower water use efficiency (WUE) than M. porteri plants. In the summer 1998 M. porteri had greater pre-dawn xylem water potentials (&amp;#968;L) than L. tridentata when soil water potentials were above -3 MPa. Larrea...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Larrea tridentata; Muhlenbergia porteri; Photosynthesis.
Ano: 2008
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1851-56572008000100025

Physiological responses of Allium cepa var. agrogarum L. plants to Cadmium stress
Provedor de dados: 85
Autores: Wang,QL; Liu,DH; Yue,JY.
This study aimed to determine the effects of different Cd concentrations (0, 1, 10, 100, and 300 µM CdCl2) on Allium plantlets. To achieve this goal, we examined the (1) dynamics of Cd2+ fux in the rhizosphere, (2) partitioning of Cd between roots and leaves, (3) formation of reactive oxygen species (ROS), (4) levels of H2O2 and chlorophyll, and (5) translocation of several macro- and micronutrients. A strong net Cd2+ influx was observed in the root apex after exposure to 100 µM Cd for 24 h. Exposure to either 1 or 10 µM Cd for 96 h presented no evident influence on root growth. However, treatments with 100 to 300 µM Cd for 72 h significantly inhibited root growth. ROS levels increased in roots and leaves with increasing Cd concentrations. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cadmium (Cd) toxicity; Net cadmium flux; ICP; Oxidative stress; Photosynthesis.
Ano: 2016
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1851-56572016000200015

Responses of Conocarpus lancifolius to environmental stress: a case study in the semi-arid land of Kuwait
Provedor de dados: 85
Autores: Redha,A; Suleman,P; Al-Hasan,R; Afzal,M.
Cococarpus lancifolius Engl. grows wild in Djibouti, Somalia and East Africa, and South Asia. The species was introduced into Kuwait, where it is exposed to several stresses: oil pollution, salinity, high temperature and harsh climatic conditions. These conditions are prevalent in its semi-arid environment. In this study, the impact of salinity (2, 6 and 10%), temperature (20, 30 and 40 °C), polyethylene glycol (10, 30 and 60%) and drought has been investigated on C. lancifolius. Proline (Pro) accumulation (5.5 ± 0.03 µg/g dry weight; p=0.05-0.005), protein (16.47 ± 0.052 mg/g; p=0.001), free amino acids (10.92 ± 0.082 mg/g; p=0.006) and lipids (116.05 ± 2.17 µg/g; p=0.05) were measured in plants irrigated with 60% polyethylene glycol (PEG) for 6 days....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Conocarpus lancifolius; Drought; Electron transport rate; Environmental stress; Salinity; Temperature; Photosynthesis.
Ano: 2012
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1851-56572012000200008

Physiological and Molecular Responses in Rice, Weedy Rice and Barnyardgrass Exposed to Supra-Optimal Temperatures
Provedor de dados: 87
Autores: OLIVEIRA,C.; AGOSTINETTO,D.; LANGARO,A.C.; GARCIA,J.R.; LAMEGO,F.P.
ABSTRACT: The global temperature to rise 0.3 to 4.8 oC to century. Supra-optimal temperatures can affect plants at different organizational levels, causing morphological, physiological, biochemical and gene expression alterations. Rice, weedy rice, and barnyardgrass may to response differently when subjected to supra-optimal temperatures. Thus, the aimed at determining the physiological response and expression of the genes APX2, HSP24.15 e HSP71.10 in rice, weedy rice, and barnyardgrass when in to supra-optimal temperatures. A greenhouse experiment was conducted in randomized complete desing with four repetitions, with a factorial combination of temperature x plantas, where: factor A consisted of two temperatures (25 oC and 40 oC); and factor B of three...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oryza sativa; Echinochloa spp.; Photosynthesis; Oxidative stress; Gene expression.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100239

Selectivity of Imazapic + Imazapyr Herbicides on Irrigated Rice as Affected by Seed Treatment with Dietholate and Clomazone Applied in Preemergence
Provedor de dados: 87
Autores: PIVETA,L.B.; PINTO,J.J.O.; AVILA,L.A.; NOLDIN,J.A.; SANTOS,L.O.
ABSTRACT: The use of dietholate seed treatment, as well as the use of preemergence clomazone, can affect the selectivity of the imidazolinones chemical group of postemergence herbicides applied in crops Clearfield™. The aim was to evaluate the morphophysiological effects of a formulated mixture of imazapyr + imazapic applied in postemergence in combination with seed treatment with dietholate and applying in preemergence of clomazone on Avaxi CL rice hybrid cultivar. The experiment was conducted in the agricultural year 2012/13, in a greenhouse. The experimental design was completely randomized in a factorial design with four replications, in which factor A consisted of seed treatment with dietholate and applied clomazone herbicide in preemergence on rice...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oryza sativa; Selectivity; Photosynthesis; Chemical control.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100261

Glyphosate influence on the physiological parameters of Conyza bonariensis biotypes
Provedor de dados: 87
Autores: Vargas,L.; Silva,D.R.O.; Agostinetto,D.; Matallo,M.B.; Santos,F.M.; Almeida,S.D.B.; Chavarria,G.; Silva,D.F.P.
The objective of this study was to determine changes in gas exchange and inhibition of EPSPs, based on the accumulation of shikimic acid in horseweed biotypes resistant and sensitive to glyphosate. Two experiments were conducted in a factorial model. The first one evaluated horseweed biotypes (one resistant and one susceptible to glyphosate), and herbicide rates (0 and 1,080 g a.e. ha ¹) applied on the weed. In the second experiment, the horseweed biotypes (susceptible and resistant to glyphosate) were evaluated in five periods as following: 0, 3, 7, 10, and 14 days after herbicide application (DAH). The photosynthetic rate, transpiration, carboxylation efficiency, and water efficiency were determined using an infrared gas analyzer (IRGA), and shikimic...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Hairy fleabane; Resistance; Photosynthesis; EPSPs; Shikimic acid.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582014000100017

Differential Tolerance of Clones of Eucalyptus grandis Exposed to Drift of the Herbicides Carfentrazone-Ethyl and Glyphosate
Provedor de dados: 87
Autores: SANTOS,S.A.; TUFFI-SANTOS,L.D.; ALFENAS,A.C.; FARIA,A.T.; SANT’ANNA-SANTOS,B.F.
ABSTRACT: Drift of the herbicides carfentrazone-ethyl and glyphosate may affect the initial growth of eucalyptus. This study aimed to assess the effect of carfentrazone-ethyl and glyphosate drift on photosynthesis, leaf morphoanatomy, and initial growth of two clones of Eucalyptus grandis. Two experiments were carried out in a 2 x 4 factorial scheme, in which factor 1 was represented by two clones of E. grandis and factor 2 by four herbicide underdoses (control, 86.4 g a.e. ha-1 of glyphosate, 3.0 g a.e. ha-1 of carfentrazone-ethyl, and the mixture of 86.4 g a.e. ha-1 of glyphosate + 3.0 g a.e. ha-1 of carfentrazone-ethyl). Herbicide application was carried out by simulating the drift in the lower third of seedling canopy. Assessments were performed 23...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Eucalyptus; Photosynthesis; Leaf morphoanatomy; Phytointoxication.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100223

INFLUENCE OF GLYPHOSATE ON SUSCEPTIBLE AND RESISTANT RYEGRASS POPULATIONS TO HERBICIDE
Provedor de dados: 87
Autores: PICOLI JR,G.J.; CARBONARI,C.A.; MATOS,A.K.A.; RODRIGUES,L.F.O.S.; VELINI,E.D.
ABSTRACT In Brazil, ryegrass (Lolium multiflorum) has been identified as resistant to glyphosate, becoming a major problem, especially in crops cultivated in the winter season. This herbicide can indirectly affect photosynthesis by inhibiting biosynthesis of many compounds. Thus, the aim of this study was to investigate the influence of glyphosate on the physiological profile of susceptible and resistant ryegrass populations to the herbicide. The experimental design was completely randomized with two treatments (720 and 1,080 g e.a. ha-1) and four replications plus control with no treatment. Two ryegrass populations were sown, one susceptible and another one resistant to glyphosate. After the treatments, evaluations were carried out at 1, 3, 7 and 28 days...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Herbicide resistance; Photosynthesis; Lolium multiflorum.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582017000100253

Efeitos da deficiência de água em plantas de Euterpe oleracea (açaí)
Provedor de dados: 88
Autores: CALBO,MARIA ELISA RIBEIRO; MORAES,JOSÉ ANTÔNIO P.V. DE.
A resistência de plantas jovens de açaí (Euterpe oleracea Mart.) à deficiência de água foi determinada em plantas de quatro meses de idade cultivadas em sacos plásticos perfurados contendo 7 kg de terra. O experimento foi conduzido em casa de vegetação e a irrigação foi suspensa até as plantas atingirem fotossíntese zero, quando, então, foram reidratadas. Durante este período foram feitas medidas diárias da fotossíntese líquida, condutância estomática e transpiração. Pequenas reduções na condutância estomática, transpiração e fotossíntese foram observadas a partir do décimo dia e se acentuaram com o tempo. A taxa de fotossíntese reduziu-se à metade da fotossíntese máxima quando o potencial de água atingiu -1,9 MPa. O estresse hídrico atingiu nível...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Euterpe oleracea; Palms; Photosynthesis; Water stress.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042000000300001

Respostas de indivíduos jovens de Tibouchina pulchra Cogn. à poluição aérea de Cubatão, SP: fotossíntese líquida, crescimento e química foliar
Provedor de dados: 88
Autores: MORAES,REGINA MARIA DE; DELITTI,WELINGTON BRAZ CARVALHO; MORAES,JOSÉ ANTÔNIO PROENÇA VIEIRA DE.
Indivíduos jovens de Tibouchina pulchra, cultivados em condições padronizadas, foram colocados em três regiões de Cubatão para estudo dos possíveis efeitos dos poluentes aéreos sobre a fotossíntese, o crescimento e as concentrações foliares de ácido ascórbico, clorofila, nitrogênio, enxofre e flúor. As áreas de estudo foram: vale do rio Pilões (RP), considerada área de referência; Caminho do Mar (CM), próxima a indústrias petroquímicas e vale do rio Mogi (VM), próxima a indústrias siderúrgicas e de fertilizantes. Quatro plantas permaneceram em cada área por um período de seis meses. Em comparação com as plantas mantidas na área de referência (RP - 9,81 mimol.m-2.s-1), a fotossíntese líquida foi reduzida (p &lt; 0,05) nas plantas que foram mantidas em VM...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Air pollution; Tibouchina pulchra; Cubatão; Photosynthesis.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042000000400010

Network connectance and autonomy analyses of the photosynthetic apparatus in tropical tree species from different successional groups under contrasting irradiance conditions
Provedor de dados: 88
Autores: Souza,Gustavo M; Ribeiro,Rafael V; Oliveira,Ricardo F. de; Machado,Eduardo C.
Biological systems are complex dynamical systems whose relationships with environment have strong implications on their regulation and survival. From the interactions between plant and environment can emerge a quite complex network of plant responses rarely observed through classical analytical approaches. The objective of this current study was to test the hypothesis that photosynthetic responses of different tree species to increasing irradiance are related to changes in network connectances of gas exchange and photochemical apparatus, and alterations in plant autonomy in relation to the environment. The heat dissipative capacity through daily changes in leaf temperature was also evaluated. It indicated that the early successional species (Citharexylum...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Dissipative structures; Functional groups; High irradiance; Network connectance; Photosynthesis.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042005000100005

Fotoinibição em três espécies do cerrado (Annona crassifolia, Eugenia dysenterica e Campomanesia adamantium ) na estação seca e na chuvosa
Provedor de dados: 88
Autores: LEMOS FILHO,JOSÉ PIRES DE.
O objetivo deste estudo foi verificar a performance fotossintética e a ocorrência de fotoinibição em três espécies do cerrado, na estação seca e estação chuvosa. Os valores do rendimento quântico potencial do fotossistema II (Fv/Fm) após 1 hora de adaptação ao escuro, ao meio dia, foram inferiores a 0,8 para todas as espécies nas duas estações, caracterizando a presença da fotoinibição. Na estação seca, apesar das reduções observadas na condutância estomática, no rendimento quântico efetivo(DF/F`m) e na taxa aparente de transporte de elétrons (ETR), a saturação da fotossíntese foi similar à observada na estação chuvosa, para todas as espécies estudadas, aproximadamente 1500 mmol.m-2.s-1. Nesse nível de luz, o excesso relativo do fluxo de fótons de...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Photoinhibition; "cerrado" plants.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042000000100005

Gas exchanges and photochemical efficiency of hydroponic bell pepper under salinity and plant density
Provedor de dados: 91
Autores: Cavalcante,Antônio R.; Santos Júnior,José A.; Furtado,Guilherme de F.; Chaves,Lúcia H. G.
ABSTRACT Gas exchanges and chlorophyll a fluorescence are ways to physiologically analyze the response of plants to salt stress. In this context, the present work was conducted between August and November 2016 in a greenhouse at the Federal University of Campina Grande (7°12’52” S, 35°54’24” W, mean altitude of 550 m), using bell pepper plants cv. All Big, exposed to levels of nutrient solution electrical conductivity (1.7, 3.7, 5.7, 7.7, 9.7 and 11.7 dS m-1) and cultivated in hydroponic system, spaced by 0.2 and 0.3 m, focusing on the analysis of gas exchanges and photochemical efficiency. The experimental design was completely randomized, in a 6 x 2 factorial scheme, with five replicates. Plant density influenced the sensitivity of the gas exchanges to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Capsicum annuum L.; Low-cost hydroponics; Photosynthesis.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662019000100003

Potassium fertilization and irrigation with treated wastewater on gas exchange of colored cotton
Provedor de dados: 91
Autores: Lima,Breno L. de C.; Silva,Ênio F. de F. e; Santos,Hugo R. B.; Souza,Edivan R. de.
ABSTRACT The use of treated domestic wastewater in agriculture is promising because it contains essential nutrients for crops, especially for cotton plants. Information on leaf gas exchanges helps to understand the responses of plants to different water and nutrient managements, since they directly affect physiological processes. Thus, the objective of this study was to evaluate the effect of potassium fertilization and irrigation with treated wastewater on the gas exchange of naturally colored cotton plants grown in the semi-arid region of the state of Pernambuco, Brazil, providing a reference for evaluations of responses of cotton plants to abiotic factors. The experiment was conducted in a randomized block design, in a 5 × 5 factorial arrangement, with...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Gossypium hirsutum L.; Photosynthesis; Stomatal conductance.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018001100741

Photosynthetic efficiency, gas exchange and yield of castor bean intercropped with peanut in semiarid Brazil
Provedor de dados: 91
Autores: Dutra,Wellison F.; Melo,Alberto S. de; Dutra,Alexson F.; Brito,Marcos E. B.; Filgueiras,Luanna M. B.; Meneses,Carlos H. S. G.
ABSTRACT To evaluate the photosynthetic efficiency, gas exchange and yield of castor bean intercropped with peanut under Brazilian semiarid conditions, a field experiment was set up with six treatments and four replicates arranged in a randomized block design. The experiment consisted of the cultivation of castor bean ‘BRS Energia’ in a monocrop system and intercropped with peanut ‘BR 1’. One treatment was formed by monocropped castor bean and the others by the castor bean intercropped with peanut with different intercrop establishment times, i.e. peanut sowing times (0, 10, 15, 20 and 25 days after castor bean sowing). The castor bean photosynthetic and carboxylation efficiencies were higher in the intercrop system with a 25-day interval between sowings....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chlorophyll fluorescence; Photosynthesis; Ricinus communis L.; Yield.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000200106

Gas exchange and photosynthetic pigments in bell pepper irrigated with saline water
Provedor de dados: 91
Autores: Melo,Hidelblandi F. de; Souza,Edivan R. de; Duarte,Heitor H. F.; Cunha,Jailson C.; Santos,Hugo R. B.
ABSTRACT The tools that evaluate the salinity effects on plants have great relevance as they contribute to understanding of the mechanisms of tolerance. This study aimed to evaluate gas exchanges and the contents of photosynthetic pigments in bell peppers cultivated with saline solutions (0, 1, 3, 5, 7 and 9 dS m-1) prepared using two sources: NaCl and a mixture of Ca, Mg, K, Na and Cl salts, in randomized blocks with a 6 x 2 factorial scheme and 4 replicates, totaling 48 experimental plots. The net photosynthesis (A), stomatal conductance (gs), transpiration (E), internal CO2 concentration (Ci), instantaneous carboxylation efficiency (A/Ci) and water use efficiency (WUE), besides chlorophyll a, b and carotenoids were evaluated. The gas exchange parameters...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Salt stress; Photosynthesis; Chlorophyll; Brazilian semi-arid region.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000100038

Gas exchange of four woody species under salinity and soil waterlogging
Provedor de dados: 91
Autores: Lima,Alan D.; Sousa,Carlos H. C.; Lacerda,Claudivan F. de; Bezerra,Marlos A.; Silva,Evandro N.; Neves,Antônia L. R.
ABSTRACT The objective of this study was to evaluate gas exchanges in seedlings of forest species grown in saline soils and subjected to soil waterlogging cycles. The experimental design was completely randomized in a factorial arrangement, with four forest species: Myracrodruon urundeuva Fr Allemão, Mimosa caesalpiniifolia Benth, Tabebuia impetiginosa (Mart. ex. DC.) Standl and Azadirachta indica A. Juss, two soil salinity levels (1.2 and 8.6 dS m-1) and two water regimes (with and without waterlogging). Measurements of stomatal conductance, transpiration and CO2 assimilation rate were performed before and after each waterlogging period. The interaction of the highest saline level (8.6 dS m-1) and waterlogging caused greater reductions in leaf gas...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Salt stress; Water excess; Caatinga.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017001000670

Gas exchange and organic solutes in forage sorghum genotypes grown under different salinity levels
Provedor de dados: 91
Autores: Coelho,Daniela S.; Simões,Welson L.; Salviano,Alessandra M.; Mesquita,Alessandro C.; Alberto,Keila da C.
ABSTRACT Adaptation of plants to saline environments depends on the activation of mechanisms that minimize the effects of excess ions on vital processes, such as photosynthesis. The objective of this study was to evaluate the leaf gas exchange, chlorophyll, and organic solute in ten genotypes of forage sorghum irrigated with solutions of different salinity levels. The experiment was conducted in a randomized block design, in a 10 x 6 factorial arrangement, with three replications, using ten genotypes - F305, BRS-655, BRS-610, Volumax, 1.015.045, 1.016.005, 1.016.009, 1.016.013, 1.016.015 and 1.016.031 - and six saline solutions, with electrical conductivity (ECw) of 0, 2.5, 5.0, 7.5, 10 and 12.5 dS m-1. The photosynthetic activity in forage sorghum plants...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Salt stress; Photosynthesis; Chlorophyll; Sorghum bicolor (L.) Moench.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018000400231

Gas exchange and leaf contents in bell pepper under energized water and biofertilizer doses
Provedor de dados: 91
Autores: Borges,Francisca R. M.; Viana,Thales V. de A.; Marinho,Albanise B.; Pinheiro Neto,Luis G.; Azevedo,Benito M. de.
ABSTRACT The objective of this study was to evaluate the effect of energized water and bovine biofertilizer doses on the gas exchange and NPK contents in leaves of yellow bell pepper plants. The experiment was conducted at the experimental area of the Federal University of Ceará, in Fortaleza-CE, Brazil, from June to November 2011. The experiment was set in a randomized block design, in a split-plot scheme; the plots were composed of treatments with energized and non-energized water and the subplots of five doses of liquid biofertilizer (0, 250, 500, 750 and 1000 mL plant-1 week-1). The following variables were analyzed: transpiration, stomatal conductance, photosynthesis and leaf contents of nitrogen (N), phosphorus (P) and potassium (K). Water...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Capsicum annuum L.; Organic fertilization; Photosynthesis.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662016000600533

Physiological responses of lima bean subjected to salt and water stresses
Provedor de dados: 91
Autores: Pereira Filho,João V.; Viana,Thales V. de A.; Sousa,Geocleber G. de; Chagas,Keivia L.; Azevedo,Benito M. de; Pereira,Carmem C. M. de S.
ABSTRACT Under water deficit and/or salt stress conditions, crops suffer from several physiological disturbances, which lead to the reduction in growth and, consequently, decreases in their yields. Thus, the objective of this study was to evaluate the physiological responses of lima bean, cultivar Espírito Santo, under different irrigation water salinity associated to two water regimes. The experiment was carried out in the experimental area of ​​the Universidade Federal do Ceará, Brazil, from September to November 2017, and it was carried out in pots in full sun, under a completely randomized design in split plots, where water salinities (1.1, 2.1, 3.1, 4.1 and 5.1 dS m-1) were considered as the plots, and the treatments of water regime (50 and 100% of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Phaseolus lunatus L.; Photosynthesis; Water quality; Water deficit.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662019001200959

Growth and gas exchanges in soursop under irrigation with saline water and nitrogen sources
Provedor de dados: 91
Autores: Silva,Evandro M. da; Lima,Geovani S. de; Gheyi,Hans R.; Nobre,Reginaldo G.; Sá,Francisco V. da S.; Souza,Leandro de P.
ABSTRACT Nitrogen (N) fertilization has been tested for the mitigation of salt stress in some species including fruit crops. However, special attention should be paid to the source of N, due to the different compositions and saline indices of the fertilizers, particularly when irrigation is conducted using waters with salinity levels that are restrictive to agriculture. Thus, this study evaluated the effect of fertilization with N sources on the growth and gas exchanges of soursop irrigated with saline water after transplanting. The experiment was carried out in greenhouse at the Center of Technology and Natural Resources of the Federal University of Campina Grande, and treatments were arranged in randomized blocks, in 4 x 4 factorial scheme, corresponding...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Annona muricata L.; Salinity; Nitrogen; Photosynthesis.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018001100776

Gas exchange alteration caused by water deficit during the bean reproductive stage
Provedor de dados: 91
Autores: Endres,Lauricio; Souza,José L. de; Teodoro,Iedo; Marroquim,Paula M. G.; Santos,Claudiana M. dos; Brito,José E. D. de.
The purpose of the present study was to analyze gas exchanges in leaves and the parameters of productivity of beans (Phaseolus vulgaris, L.) submitted to two water deficiency periods during which three water regimes were employed: W1 (1,0 ETo during the entire plant cycle); W2 (1,0 ETo up to the flowering period and irrigation interruption from the 37 to the 51st day following sowing, and W3 (in addition to the reproductive phase, water deficit was also applied during the vegetative stage). Photosynthesis was one of the main physiological factors affected by water deficit. This was not only caused by the stomata closure, but also by carboxilation reduction due to metabolic damage. This effect was, however, offset 24 h after rehydration. During flowering,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Transpiration; Phaseolus vulgaris L.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662010000100002

Fluorescence of chlorophyll a and photosynthetic pigments in Atriplex nummularia under abiotic stresses
Provedor de dados: 91
Autores: Melo,Hidelblandi F. de; Souza,Edivan R. de; Cunha,Jailson C.
ABSTRACT Chlorophyll a fluorescence is a very useful tool in ecophysiological studies to analyze the photosynthetic performance of plants under biotic and abiotic stresses. This research aimed to evaluate the parameters of the fluorescence of chlorophyll a, contents of chlorophyll a, b and total, and carotenoids in Atriplex nummularia cultivated under water stress (37 and 70% of field capacity) and salt stress (irrigation water with electrical conductivity of 0, 5, 10, 20, 30 and 40 dS m-1), besides two sources of salts: NaCl and a mixture of salts of Ca2+, Mg+2, K+, Na+ and Cl-, in a 6 x 2 x 2 factorial, with 4 replicates, totaling 96 experimental plots. At 91 days after transplanting, the initial fluorescence (F0), maximum fluorescence (Fm), potential...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Water and salt stress; Halophyte.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000400232

Leaf gas exchange in cowpea and CO2 efflux in soil irrigated with saline water
Provedor de dados: 91
Autores: Oliveira,Wanderson J. de; Souza,Edivan R. de; Cunha,Jailson C.; Silva,Ênio F. de F. e; Veloso,Venâncio de L.
ABSTRACT Leaf gas exchanges in plants and soil respiration are important tools for assessing the effects of salinity on the soil-plant system. An experiment was conducted with cowpea irrigated with saline water (0, 2.5, 5.0, 7.5, 10.0 and 12.5 dS m-1) prepared with two sources: NaCl and a mixture of Ca, Mg, Na, K and Cl ions in a randomized block design and a 6 x 2 factorial scheme, with four replicates, totaling 48 experimental plots. At 20 days after planting (DAP), plants were evaluated for net photosynthesis (A), stomatal conductance (gs) and transpiration (E) using the Infra-Red Gas Analyzer (Model XT6400- LICOR), and water use efficiency, intrinsic water use efficiency and instantaneous efficiency of carboxylation were calculated. At 60 DAP, the soil...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Salinity; Salt stress; Soil respiration.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000100032

Irrigation with saline water in soybean (Glycine max (L.) Merr.) in a soil with bovine biofertilizer
Provedor de dados: 91
Autores: Sousa,Geocleber G. de; Rodrigues,Valdécio dos S.; Soares,Stallone da C.; Damasceno,Ítalo N.; Fiusa,Jamili N.; Saraiva,Sâmara E. L.
ABSTRACT Salinity is a complex phenomenon that affects the metabolic processes of the plant, changing the physiological and biochemical parameters. In this context, the objective of this study was to evaluate the effect of irrigation water salinity on growth, biomass and gas exchanges in soybean crop in soil with and without biofertilizer. The experiment was carried out in a greenhouse at the experimental area of ​​the Agrometeorological Station of the UFC, Fortaleza, CE, Brazil, from May to June 2016. The treatments were distributed in randomized blocks in a 5 × 2 factorial scheme, corresponding to the levels of irrigation water salinity: 0.8; 1.6; 2.4; 3.2 and 4.0 dS m-1, in soil without and with bovine biofertilizer, in five replicates. The following...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Organic fertilizer; Saline stress; Photosynthesis.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018000900604

Defoliation of sweet corn plants under irrigation depths and its impact on gas exchange
Provedor de dados: 91
Autores: Santos,Osvaldir F. dos; Lima,Sebastião F. de; Paiva Neto,Vespasiano B. de; Piati,Gabriel L.; Osório,Christian R. W. de S.; Souza,Hugo M. de.
ABSTRACT The objective of this work was to evaluate leaf gas exchanges of sweet corn as a function of defoliation when submitted to different irrigation depths. The experimental design was randomized blocks in split-plot scheme, with four irrigation depths in the plots [50, 75, 100 and 125% of crop evapotranspiration (ETc)], and three levels of defoliation in the subplots (0%, control; 35%, removal of four fully expanded leaves; 100%, total removal of the leaves - section of the aerial part) with three replicates. Defoliation was manually performed when the plant had four fully expanded leaves. It was verified that the dephs of irrigation and defoliation levels affect leaf gas exchanges in sweet corn plants, allowing the conclusion that the plant tends to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Zea mays L. var. saccharata; Water stress; Photosynthesis.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017001200822

Influence of mechanical root restriction on gas-exchange of four papaya genotypes
Provedor de dados: 93
Autores: CAMPOSTRINI,ELIEMAR; YAMANISHI,OSVALDO KIYOSHI.
Four papaya genotypes, two from the ‘Solo’ group (Sunrise Solo TJ and Improved Sunrise Solo line 72/12) and two from the ‘Formosa’ group (Tainung 02 and Know You 01) grown in ultisol under field conditions in Macaé, RJ, Brazil, were used in this study. Two different effective depths (ED) were determined in the area using a penetrographer with average soil moisture of 11.2%. The area with ED of 0.35 m with a maximum pressure of 4.12 MPa for penetration was defined as an area with restriction (WR) to root growth, while, the area with minimum ED of 0.60 m and a pressure lower than 2.30 MPa as an area with no restriction (NR). The net CO2 assimilation rate (A), stomatal conductance (g s), leaf temperature (Tl), intercellular partial pressure of CO2 (c i) and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Carica papaya L.; Photosynthesis; Leaf temperature; Stomatal conductance; Intrinsic water use efficiency.
Ano: 2001
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-31312001000200002

IS Annona emarginata CAPABLE OF ACCUMULATE ESSENTIAL HEAVY METALS WITHOUT DAMAGES IN THE METABOLISM?
Provedor de dados: 94
Autores: BARON,DANIEL; AMARO,AMANDA CRISTINA ESTEVES; MACEDO,ANA CLAUDIA; BOARO,CARMEN SÍLVIA FERNANDES; FERREIRA,GISELA.
ABSTRACT  This study aimed to evaluate if ionic strength variation causes differential accumulation of heavy metals in plants of Annona emarginata (Schltdl.) H. Rainer var. ‘terra-fria’, modifying gas exchange and dry matter production. The seedlings were cultivated under different ionic strengths of the ‘Hoagland and Arnon’s’ nutrient solution (75% I, 50% I and 25% I). At 180 days after the application of the treatments, the effects of the essential heavy metals on the physiological parameters and foliar ionic concentration were assessed. The leaf gas exchanges and vegetative growth were affected by the variation in the essential heavy metals, with positive effects on the plants that were treated with 75%I. The seedlings that were grown under 75% I...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Heavy metals; Ionic strength; Mineral nutrition; Photosynthesis.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452017000400202

Water status and gas exchange of umbu plants (Spondias tuberosa Arr. Cam.) propagated by seeds and stem cuttings
Provedor de dados: 94
Autores: Lima Filho,José Moacir Pinheiro.
The experiment was carried out at the Embrapa Semi-Árido, Petrolina-PE, Brazil, in order to study the physiological responses of umbu plants propagated by seeds and by stem cuttings under water stress conditions, based on leaf water potential and gas exchange measurements. Data were collected in one-year plants established in pots containing 30 kg of a sandy soil and submitted to twenty-day progressive soil water deficit. The evaluations were based on leaf water potential and gas exchange data collection using psychrometric chambers and a portable infra-red gas analyzer, respectively. Plants propagated by seeds maintained a significantly higher water potential, stomatal conductance, transpiration and photosynthesis under decreasing soil water availability....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Water potential; Stomatal conductance; Transpiration; Photosynthesis; Root tubers.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452007000200032

LEAF GAS EXCHANGE CHARACTERISTICS OF FOUR PAPAYA GENOTYPES DURING DIFFERENT STAGES OF DEVELOPMENT
Provedor de dados: 94
Autores: CAMPOSTRINI,ELIEMAR; YAMANISHI,OSVALDO KIYOSHI; MARTINEZ,CARLOS A.
In this research, was used four papaya (Carica papaya L.) genotypes: three from the 'Solo ( Sunrise Solo TJ, Sunrise Solo 72/12 and Baixinho de Santa Amália) group and one from the 'Formosa' group (Know-You 01). They were grown in plastic pots containing a sandy-clay-loam soil subjected to pH correction and fertilization, under greenhouse conditions. Throughout the experimental period plants were subjected to periodic irrigation to maintain the soil humitidy around field capacity. The experiment was conducted 73 days after sowing. In all genotypes, leaf gas exchange characteristics were determined. The net photosynthetic rate (A, mumol m-2 s-1 ), stomatal conductance (g s mol m-2 s-1), leaf temperature (T I, 0C) and intercellular carbon dioxide...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Carica papaya; Stomatal conductance; Leaf temperature.
Ano: 2001
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452001000300014

Gas exchange of the umbu tree under semi-arid conditions
Provedor de dados: 94
Autores: Lima Filho,José Moacir Pinheiro.
A study was carried out at Embrapa Semi-Árido, Petrolina-PE, Brazil, aiming to understand the gas exchange process of the umbu tree (Spondias tuberosa Arr. Cam.) in the dry and rainy seasons. Stomatal conductance, transpiration, photosynthesis and internal CO2 concentration were obtained with a portable infrared gas analyzer (IRGA). During the dry season the umbu tree showed a much lower stomatal conductance early in the morning, as soon as the vapor pressure deficit increased, apparently affecting CO2 assimilation more than transpiration. The highest values were detected around 6:00 am but decreased to the lowest points between 10:00 am and 2:00 pm. During the rainy season, however, stomatal conductance, transpiration and photosynthesis were significantly...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Spondias tuberosa; Stomatal conductance; Transpiration; Photosynthesis; CO2 internal concentration.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452004000200006

Gas exchanges in annonaceae species under different crop protections
Provedor de dados: 94
Autores: Baron,Daniel; Ferreira,Gisela; Rodrigues,João Domingos; Macedo,Ana Claudia; Amaro,Amanda Cristina Esteves.
This study aims to investigate the gas exchanges of different species of Annonaceae due to environmental variations provided by different types of crop protection. 'Araticum-de-terra-fria', 'araticum-mirim', 'biribá' and atemoya seedlings were cultived in three different crop protections: nursery, greenhouse and warm house. Gas exchanges were obtained in six plants, from 9:00 am to 11:00 am, with IRGA, LI-6400, at 180 Days After Transplanting. The different types of crop protection had a direct influence on gas exchanges of these species. Thus, nursery provided suitable conditions for 'araticum-de-terra-fria', 'araticum-mirim' and 'biribá', increasing their gas exchanges. To atemoya the best crop protection was the greenhouse.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Environmental condition; Annona emarginata; Annona mucosa; Annona squamosa L. x Annona cherimola Mill.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452014000500028

Foliar gas exchange, fruit quality and water use efficiency of cape Gooseberry under different irrigation depths and mulching at greenhouse conditions
Provedor de dados: 94
Autores: Barbosa,Eduardo Augusto Agnellos; Ayub,Ricardo Antonio; Luz,Ângela da; Pessenti,Isabela Leticia; Pereira,André Belmont.
Abstract  The current study aimed at evaluating gas exchanges, yield, water use efficiency and fruit quality of cape gooseberry in response to different irrigation depths with or without mulching of oat residues on pots at greenhouse conditions. Four irrigation depths were tested: 50%, 100%, 125% e 150% of reference evapotranspiration (ETo). Leaf gas exchanges were evaluated by an infrared gas analyzer at different stages of the crop. Throughout the harvest, yield per plant and yield components were assessed in conjunction with water-use efficiency (WUE) and fruit quality responses. Stomata conductance at the flowering and fructification stages showed a smaller limitation under the treatments 125 and 150%ETo. It should be noticed that the aforementioned...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Physalis peruviana L.; Water stress; Stomata conductance; Photosynthesis; Fruit yield.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452019000406001

EVALUATION OF GAS EXCHANGES IN DIFFERENT Prunus SPP. ROOTSTOCKS UNDER DROUGHT AND FLOODING STRESS
Provedor de dados: 94
Autores: KLUMB,ELSA KUHN; RICKES,LETICIA NEUTZLING; BRAGA,EUGENIA JACIRA BOLACEL; BIANCHI,VALMOR JOÃO.
ABSTRACT  The state of Rio Grande do Sul is the largest peach productor in Brazil; however, it still possesses poor yield values when compared with other states. One of the problems associated with this is the occurrence of soils with drainage problems, mainly in Pelotas region, which depending on the year period, may undergo water deficit or flooding situations in the great majority of the years, which harm the crop development and yield. Among the harmful effects caused by these stresses stand out, the decrease in the net assimilation rate, closure of stomata, reduction of the cell activities, production of reactive oxygen species, membrane and protein destabilization. Thus, the aim of this study was to investigate in what magnitude of the gaseous...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Water stress; Photosynthesis; Peach tree; Plum tree.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452017000400706

Responses of six Brachiaria spp. accessions to root zone flooding
Provedor de dados: 96
Autores: Caetano,Luana Pabla de Souza; Dias-Filho,Moacyr Bernardino.
Some morphophysiological responses of Brachiaria brizantha cv. Marandu, cv. Piatã, cv. Arapoty, B163, B166 and B. ruziziensis R124 were compared in plants grown in pots, under flooded and well-drained conditions. Flooding reduced leaf elongation rate in all accessions. Leaf dry mass production was lower under flooding than in the control plants in all the studied accessions, except in cv. Piatã. Root dry mass production was reduced by flooding in cv. Marandu and in R124, while the proportion of biomass allocated to roots was reduced by flooding only in R124. It was not possible to detect significant differences between water regimes in the percentage of biomass allocated to culms and leaves for all accessions. Flooding decreased the number of tillers in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Biomass allocation; Brachiaria brizantha; Leaf elongation rate; Photosynthesis; Relative growth rate.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982008000500003

Gas exchange in massai grass under five nitrogen fertilization levels during establishment and regrowth
Provedor de dados: 96
Autores: Lopes,Marcos Neves; Lacerda,Claudivan Feitosa de; Cândido,Magno José Duarte; Pompeu,Roberto Cláudio Fernandes Franco; Silva,Rodrigo Gregório da; Lopes,José Wellington Batista; Fernandes,Francisco Ronaldo Belém; Bezerra,Francisco Marcus Lima.
The objective of this study was to evaluate gas exchange in the massai grass during establishment and regrowth cycles in a greenhouse, using five nitrogen (N) fertilization levels. A completely randomized split-plot design of five nitrogen levels (0; 150; 300; 450 and 600 mg N•dm-3 of soil) was employed with the N levels as plots, and the cycles (establishment, regrowth 1 and 2) as subplots, evaluated with five replicates. We evaluated leaf transpiration (E), leaf temperature (TFOL), leaf photosynthesis rate (A), leaf carbon dioxide concentration (Ci), stomatal conductance (gs), photosynthesis/transpiration ratio (A/E), photosynthesis/conductance ratio (A/gs), chlorophyll relative index (CRI), and nitrogen sufficiency index (NSI). Growth cycles influenced...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chlorophyll; CO2 concentration; Panicum maximum; Photosynthesis.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982011000900004

Sensitivity of winter phytoplankton communities from Andean lakes to artificial ultraviolet-B radiation
Provedor de dados: 97
Autores: HELBLING,E. WALTER; VILLAFAÑE,VIRGINIA E.; BARBIERI,ELENA S.
During July of 1999 sampling was carried out in five Andean lakes to determine the sensitivity of winter phytoplankton communities to ultraviolet-B radiation (UV-B, 280-320 nm). The studied lakes, Moreno, El Trébol, Nahuel Huapi, Gutiérrez, and Morenito, located in the Patagonia region (41° S, 71° W, 800 m of altitude), had attenuation coefficients for UV-B that ranged from 0.36 m-1 (Lake Moreno) to 2.8 m-1 (Lake Morenito). The samples were inoculated with labeled carbon (NaH14CO3) and incubated in an illuminated chamber (UV-B = 0.35 W m-2, UV-A [320-400 nm] = 1.1 W m-2, and PAR [400-700 nm] = 10.8 W m-2) at 10 °C. The phytoplankton cells were exposed to UV radiation (280-400 nm) + PAR (quartz tubes), and to UV-A + PAR (quartz tubes covered with Mylar-D)....
Tipo: Journal article
Palavras-chave: Ultraviolet-B radiation; Photosynthesis; Phytoplankton; Ozone; Andean lakes.
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2001000200005

Seasonal changes in the photosynthetic performance of two evergreen Nothofagus species in south central Chile
Provedor de dados: 97
Autores: ZÚÑIGA,RAFAEL; ALBERDI,MIREN; REYES-DÍAZ,MARJORIE; OLIVARES,ERICK; HESS,SUSAN; BRAVO,LEÓN A; CORCUERA,LUIS J.
The evergreen Nothofagus dombeyi and Nothofagus nitida are important members of the temperate Chilean rainforest. They seldom grow together in nature. Nothofagus nitida is more susceptible to excess light and drought than N. dombeyi. We postulate that the different properties of the photosynthetic apparatus under common garden conditions of these species could explain their contrasting habitat preferences. The two species growing in a common garden in south central Chile were studied. The optimal photochemical efficiency (Fv/Fm) of both species remained within normal values (»0.8) with the exception of a decrease in N. dombeyi at midday in summer, suggesting reversible reduction in photochemical efficiency of photosystem II (PSII). During summer the...
Tipo: Journal article
Palavras-chave: Chlorophyll fluorescence; Photosynthesis; Nothofagus dombeyi; Nothofagus nitida; Xanthophyll cycle.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2006000400008

Ecophysiological strategies in response to UV-B radiation stress in cultures of temperate microalgae isolated from the Pacific coast of South America
Provedor de dados: 97
Autores: MONTECINO,VIVIAN; MOLINA,XIMENA; MARTÏNEZ,GINGER; OLMEDO,M. ISABEL; RETAMAL,LEIRA; HANNACH,GABRIELA; ORELLANA,MÓNICA V.
Marine microalgae exposed to ultraviolet radiation (UV) have complex adaptive responses provided by a series of protection and repair mechanisms. Interspecific differences in UV sensibility could result in differential selection of the more tolerant species, having consequences for the structure of phytoplankton assemblages. The relative importance of protection and photorepair mechanisms of microalgal cells exposed to potential UV-B stress was studied in monocultures with different taxonomic, ecological and size characteristics obtained from the Chilean coast. Differences in photosynthesis and growth rates were predicted, since the ability to effectively acclimate to UV is not universal between microalgal species. The dinoflagellate Alexandrium catenella...
Tipo: Journal article
Palavras-chave: Photosynthesis; Absorbance; Photoreactivation; Growth; UV response.
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2001000200007

Photosynthetic responses to temperature and light of Antarctic and Andean populations of Colobanthus quitensis (Caryophyllaceae)
Provedor de dados: 97
Autores: SIERRA-ALMEIDA,ÁNGELA; CASANOVA-KATNY,M. ANGÉLICA; BRAVO,LEÓN A; CORCUERA,LUIS J; CAVIERES,LOHENGRIN A.
Colobanthus quitensis (Kunth, 1831) Bartling (Caryophyllaceae) is characterized by a wide latitudinal distribution, ranging between the tropical high Andes and the Antarctic Peninsula. Although both habitat types are characterized by cold and freezing temperatures, important microclimatic differences exist during the growing season. Hence, important differences in the response of the photosynthetic apparatus to abiotic factors could be expected between Antarctic and Andean populations of C. quitensis. We studied the relationship between net photosynthesis, leaf temperature and light intensity in two populations of C. quitensis, one from La Parva in the Andes of central Chile and the other from King George Island, in the Maritime Antarctic. Plants from both...
Tipo: Journal article
Palavras-chave: Photosynthesis; Colobanthus quitensis; Optimum leaf temperature; Light intensity.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2007000300007

Photochemical efficiency of PSII and photoprotective pigments in seedlings and adults of two Proteaceae with different shade tolerance from the Chilean temperate rain forest
Provedor de dados: 97
Autores: ALBERDI,MIREN; REYES-DÍAZ,MARJORIE; ZÚÑIGA,RAFAEL; HESS,SUSAN; BRAVO,LEÓN A; CORCUERA,LUIS J.
The seasonal variation in energy quenching parameters of photosystem II and photoprotective pigments were studied in seedlings and adults of two Proteaceae: a shade-intolerant species (Embotrium coccineum J.R. et G. Forster) and a shade-tolerant species (Lomatia ferruginea (Cav.) R. Br.). We postúlate that the shade intolerant species favors photochemical energy driven processes (mainly C0(2) assimilation) while the shade tolerant species exhibits higher non-photochemical energy dissipation under unfavorable conditions. Moreover, the shade tolerant species presents lower seasonal variations in these parameters that the shade intolerant species. Differences in energy dissipation should be more evident in seedlings than adults because of their contrasting...
Tipo: Journal article
Palavras-chave: Chlorophyll fluorescence; Lutein; Photosynthesis; Photoprotective pigments; Xanthophyíls cycle.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2009000300006

Ecophysiology of Antarctic macroalgae: effects of environmental light conditions on photosynthetic metabolism
Provedor de dados: 97
Autores: GÓMEZ,I.
Daylength is the major environmental factor affecting the seasonal photosynthetic performance of Antarctic macroalgae. For example, the "season anticipation" strategy of large brown algae such as Ascoseira mirabilis and Desmarestia menziesii are based on the ability of their photosynthetic apparatus to make use of the available irradiance at increasing daylengths in late winter-spring. The seasonal development and allocation of biomass along the lamina of A. mirabilis are related to a differential physiological activity in the plant. Thus, intra-thallus differentiation in O2-based photosynthesis and carbon fixation represents a morpho-functional adaptation that optimizes conversion of radiant energy to primary productivity. In Desmarestia menziesii,...
Tipo: Journal article
Palavras-chave: Polar macroalgae; Antarctic; Photosynthesis; Daylength.
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2001000200004

Enzymatic regulation of photosynthetic and light-independent carbon fixation in Laminaria setchellii (Phaeophyta), Ulva lactuca (Chlorophyta) and Iridaea cordata (Rhodophyta)
Provedor de dados: 97
Autores: CABELLO-PASINI,ALEJANDRO; ALBERTE,RANDALL S.
Carbon is acquired through photosynthetic and non-photosynthetic processes in marine algae. However, little is known about the biochemical regulation of these metabolic pathways along the thallus of seaweeds. Consequently, the objective of this study was to assess the distribution of in vivo carboxylation pathways and to relate them to the in vitro activity of ribulose 1,5-bisphosphate carboxylase/oxygenase (RUBISCO), phosphoenolpyruvate carboxykinase (PEPCK), and phosphoenolpyruvate carboxylase (PEPC) in the Phaeophyte Laminaria setchellii, the Chlorophyte Ulva lactuca, and the Rhodophyte Iridaea cordata. Chlorophyll-a levels did not vary in U. lactuca and I. cordata. However, pigment levels were significantly lower in the meristematic region of L....
Tipo: Journal article
Palavras-chave: Enzymatic activity; Chlorophyll; Light-independent carbon fixation; Photosynthesis.
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2001000200002

Photosynthetic UV stress tolerance of the Antarctic snow alga Chlorella sp. modified by enhanced temperature?
Provedor de dados: 97
Autores: Rivas,C.; Navarro,N.; Huovinen,P.; Gómez,I.
BACKGROUND: Photosynthetic characteristics and the effect of UV radiation and elevated temperature measured were studied in Chlorella sp. isolated from a snow microalgal community at King George Island, Maritime Antarctica through the chlorophyll florescence (rapid light curves and maximum quantum yield, respectively). The environmental context was monitored through measurements of spectral depth profiles of solar radiation (down to 40 cm) in the snowpack as well as a through continuous recording of temperature and PAR using dataloggers located at different depths (0-30 cm) within the snow column RESULTS: The photochemistry of Chlorella sp. was affected by UV radiation in a 12-h laboratory exposure under all studied temperatures (5, 10, 15, 20 °C): the...
Tipo: Journal article
Palavras-chave: Antarctica; Snow algae; Chlorella sp; Photosynthesis; UV radiation; Temperature.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2016000100006

Photosynthetic responses to UV-radiation of intertidal macroalgae from the Strait of Magellan (Chile)
Provedor de dados: 97
Autores: RAUTENBERGER,RALF; MANSILLA,ANDRÉS; GÓMEZ,IVÁN; WIENCKE,CHRISTIAN; BISCHOF,KAI.
For the first time, the photosynthetic performance of field-grown macroalgae from the Magellan Strait was evaluated with respect to their photoadaptation in the field and acclimation potential to ultraviolet radiation. Five macroalgal species were collected in the eulittoral and the upper sublittoral: Ulva intestinalis, Porphyra columbina, Adenocystis utricularis, Desmarestia confervoides and D. ligulata. Photosynthesis vs. irradiance (P-I) curves of macroalgae cultivated in the laboratory under low white light intensities more than a week were used to assess the acclimation potential to irradiance conditions in the field. Both, photosynthetic parameters referred to as maximum electron transport rate (ETRmax) and light saturation points of photosynthesis...
Tipo: Journal article
Palavras-chave: UV-radiation; Macroalgae; Photosynthesis; Photoacclimation; Strait of Magellan.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2009000100003

Photosynthetic pigments and gas exchange in red and green cabbage under no-tillage and conventional systems
Provedor de dados: 124
Autores: Echer,Márcia de Moraes; Guimarães,Vandeir Francisco; Inagaki,Adriano Mitio; Dalastra,Graciela Maiara; Hachmann,Tiago Luan.
ABSTRACT The aim of the present study was to verify changes in the levels of photosynthetic pigments as well as gas exchange in the Fuyutoyo and Red Cabbage cultivars, grown under no-tillage (NT) and conventional (CT) systems. A randomised block design with four replications was used, in a 2 x 2 factorial scheme, where the Fuyutoyo and Red Cabbage cultivars were evaluated under two tillage systems. The levels of chlorophyll a, chlorophyll b, total chlorophyll and anthocyanins in the leaves were evaluated in triplicate. Localised gas exchange was measured at different times of the day, together with different photosynthetic photon flux density curves (PPFD). The Fuyutoyo cultivar showed a higher mean value for chlorophyll a (34.58%), chlorophyll b (35.09%)...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Net CO2 assimilation rate; Crop management; Brassica oleracea var. capitata.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902020000200416

Growth and productivity of lettuce cultivars under protected environment with and without thermal reflector screen
Provedor de dados: 22
Autores: Gonçalves-Trevisoli, Edilaine Della Valentina; Dartora, Janaína; Mendonça, Heloísa Ferro Constâncio; Rissato, Bruna Broti; Dildey, Omari Dangelo Forlin; Coltro-Roncato, Sidiane; Santana, José Carlos de; Klosowski, Élcio Silvério; Echer, Marcia de Morais; Tsutsumi, Cláudio Yuji.
The aim of the work was to evaluate the growth and productivity of lettuce cultivars cultivated in greenhouse with and without thermo-reflective screens. The experiment was conducted in greenhouse in Assis Chateaubriand, Paraná State. The experimental design was in a randomized block design with six replications and treatments arranged in a 2 x 4 factorial. The first factor consisted of culture environments (with and without thermo-reflective screens 50%) and the second of four cultivars of lettuce (Itapuã, Paola, Vera and Verônica). Five samples were performed weekly for evaluation of dry matter and leaf area used to obtain the absolute and relative growth rates, net assimilation rates, leaf area ratio and specific leaf area. At the last evaluation were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Growth analysis; Photosynthesis; Lactuca sativa L.; Solar radiation.
Ano: 2017
URL: http://e-revista.unioeste.br/index.php/scientiaagraria/article/view/14033

Gas exchange in Annona emarginata (Schltdl.) H. Rainer subjected to salt stress and application of plant growth regulator
Provedor de dados: 22
Autores: Dalanhol, Samanta Jaqueline; Mantoan, Luís Paulo Benetti; Amaro, Amanda Cristina Esteves; Ferreira, Gisela.
The aim of this study was to evaluate the effects of the application of plant growth regulator on gas exchange in A. emarginata seedlings subjected to different NaCl concentrations. We evaluated the gas exchange in A. emarginata seedlings subject to the presence and absence of plant growth regulator consisting of kinetin, gibberellic acid, and indolbutyric acid and three concentrations of NaCl (0 mM, 50 mM, and 100 mM). When assessing these factors individually, it was observed that in the presence of plant growth regulators, there was a reduction in stomatal conductance and transpiration, and NaCl concentration (50 mM and 100 mM) caused a reduction in CO2 assimilation, stomatal conductance, and transpiration. There was no significant interaction between...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Auxin; Cytokinin; Gibberellin; Photosynthesis; Sodium chloride.
Ano: 2018
URL: http://e-revista.unioeste.br/index.php/scientiaagraria/article/view/16139

Use of light-emitting diode (LED) in the physiology of cultivated plants – review
Provedor de dados: 22
Autores: Lazzarini, Luiz Eduardo Santos; Pacheco, Fernanda Ventorim; Silva, Samia Torres; Coelho, Adriane Duarte; Medeiros, Ana Paula Ribeiro; Bertolucci, Suzan Kelly Vilela; Pinto, José Eduardo Brasil Pereira; Soares, Joyce Doria Rodrigues.
The objective of this study was to demonstrate the effects of the use of LED bulbs in the physiology of cultivated plants. Light-emitting diodes (LEDs) have been proposed as a light source for controlled environments or in plant growth chambers, since they have desirable characteristics for plant development. The development and physiology of plants are strongly influenced by the environment light spectrum provided by the LEDs, among which we can mention the blue, red, green, and their combinations. The blue light, for example, is responsible for a number of important photomorphogenetic features in plants, including stomatal control. Studies indicate that the red wavelength is efficiently absorbed by the pigments present in the plants, since its wavelength...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chlorophyll; Light energy; Light spectrum; Photosynthesis; Pigments.
Ano: 2017
URL: http://e-revista.unioeste.br/index.php/scientiaagraria/article/view/16972

Early defoliation effects on water status, fruit yield and must quality of ‘Nerello mascalese’ grapes
Provedor de dados: 63
Autores: Ferlito,Filippo; Allegra,Maria; Torrisi,Biagio; Pappalardo,Helena; Gentile,Alessandra; Malfa,Stefano La; Continella,Alberto; Stagno,Fiorella; Nicolosi,Elisabetta.
ABSTRACT: The effect of basal zone defoliation on vines influences yield and ripening depending on the phenological stage and its intensity. Early basal defoliation (EBD) was carried out at flowering on the autochthonous Vitis vinifera (L.) cultivar ‘Nerello mascalese’ grown on the eastern slopes of Mount Etna, Sicily. The effects were evaluated over a two-year period. In the first year, the canopy retained 67 % of its original leaf area after EBD and in the second year, 58 %. Compared with control vines, mid-day leaf water potentials in the EBD vines enjoyed higher water status throughout the growing seasons in both years. EBD had no significant negative effects on yield but did have significant positive effects on the levels of total polyphenols, total...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Vitis vinifera (L.); Photosynthesis; Canopy; Sustainability; Berry quality.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162020000600602

Salinity reduced growth PS2 photochemistry and chlorophyll content in radish
Provedor de dados: 63
Autores: Jamil,Muhammad; Rehman,Shafiq ur; Lee,Kui Jae; Kim,Jeong Man; Kim,Hyun-Soon; Rha,Eui Shik.
When plants are grown under saline conditions, photosynthetic activity decreases leading to reduced plant growth, leaf area, chlorophyll content and chlorophyll fluorescence. Seeds and seedlings of radish (Raphanus sativus L.) were grown in NaCl solutions under controlled greenhouse conditions. The NaCl concentrations in complete nutrient solutions were 0 (control), 4.7, 9.4 and 14.1 dS m-1. The salinity reduced germination percentage and also delayed the germination rate as the salt level increased. Lengths and fresh weights of root and shoot decreased with the increasing salt concentration. Furthermore, photochemical efficiency of PS2 (Fv/Fm), photochemical quenching coefficient (qP), non photochemical quenching coefficient (qN), leaf area and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Raphanus sativus L.; Plant growth; Photosynthesis; Leaf area.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162007000200002

Cotton response to mepiquat chloride and temperature
Provedor de dados: 63
Autores: Rosolem,Ciro A.; Oosterhuis,Derrick M.; Souza,Fabio S. de.
Gibberellin inhibitor growth regulators are used for cotton (Gossypium hirsutum L.) canopy manipulation to avoid excess growth and yield losses. However, under temperatures below or over the optimum for cotton production the effect of mepiquat chloride (MC) has not always been significant. In this experiment, cotton plants were grown in growth chambers to study the response to MC as affected by temperature and to determine if an increase in dose could overcome the temperature effects. Mepiquat chloride was applied at rates of 0, 15 and 30 g ai ha-1 at the pinhead square stage. Plants were then grown under three temperature regimes: 25/15 °C, 32/22 °C, and 39/29 °C (day/night temperatures) for 51 days. Higher temperatures increased plant height,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Plant growth regulator; Cotton growth; Photosynthesis.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162013000200004

Carbohydrate production and transport in cotton cultivars grown under boron deficiency
Provedor de dados: 63
Autores: Bogiani,Julio Cesar; Amaro,Amanda Cristina Esteves; Rosolem,Ciro Antonio.
An adequate supply of boron (B) is required for the optimal growth and development of cotton (Gossypium hirsutum L.) plants, but the low phloem mobility of B limits the possibilities of correcting B deficiency. There are indications that different cotton cultivars could have different responses to B deficiency. The differences in responses of cotton cultivars to B regarding photoassimilate production and transport were studied in a greenhouse experiment with nutrient solution. Treatments consisted of three cotton cultivars (FMT 701, DP 604BG and FMX 993) and five concentrations of B (0.0, 2.5, 5.0, 10.0 and 20.0 µmol L−1). Sampling began at the phenological stage B1 (first square) and continued for four weeks. The leaf area and the number of reproductive...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Micronutrient; Nonstructural carbohydrates; Photosynthesis; Transpiration.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162013000600010

Differential leaf gas exchange performance of mango cultivars infected by different isolates of Ceratocystis fimbriata
Provedor de dados: 63
Autores: Bispo,Wilka Messner da Silva; Araujo,Leonardo; Moreira,Wiler Ribas; Silva,Leandro de Castro; Rodrigues,Fabrício Ávila.
ABSTRACT Caused by the vascular fungus Ceratocystis fimbriata, mango wilt is considered to be one of the most serious threats in mango-producing regions worldwide. However, changes in leaf gas exchange level and the mechanisms underlying host responses to this fungal infection remain poorly described. This study aimed to evaluate potential changes in the leaf gas exchange of different mango cultivars (Ubá, Espada, Haden and Tommy Atkins) in response to two Brazilian isolates of C. fimbriata (CEBS15 and MSAK16) to non-invasively assess cultivar variability in relation to the basal level of resistance to mango wilt. Both isolates, regardless of the cultivar, caused reductions in stomatal conductance and, thus, a reduction in CO2 assimilation via diffusive...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Mangifera indica; Mango wilt; Photosynthesis; Vascular disease.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162016000200150

Oxidative damage and photosynthetic impairment in tropical rice cultivars upon exposure to excess iron
Provedor de dados: 63
Autores: Pinto,Samuel de Souza; Souza,Anna Elisa de; Oliva,Marco Antonio; Pereira,Eduardo Gusmão.
ABSTRACT Iron plays a pivotal role in the redox reactions of photosynthesis and metabolic processes such as chlorophyll synthesis. Iron availability in waterlogged soils can reach toxic levels and promote oxidative stress. Fe toxicity is the most concerning of stresses for rice in many lowland environments around the world and may cause severe impairments in rice photosynthesis. This study aimed to investigate the extension of oxidative stress after excess Fe exposure and its effects on the photosynthesis of rice cultivars with differential sensitivity. Three Brazilian rice cultivars (EPAGRI 107, BRSMG SELETA and BR IRGA 409) were grown in Hoagland nutrient solution (pH 4.0) with two Fe-EDTA doses corresponding to excess Fe (7 mM) and control (0.009 mM)...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: TBARS; Iron toxicity; Light energy dissipation; Oxidative stress; Photosynthesis.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162016000300217

Plant densities and modulation of symbiotic nitrogen fixation in soybean
Provedor de dados: 63
Autores: Luca,Marcos Javier de; Hungría,Mariangela.
Soybean nitrogen (N) demands can be supplied to a large extent via biological nitrogen fixation, but the mechanisms of source/sink regulating photosynthesis/nitrogen fixation in high yielding cultivars and current crop management arrangements need to be investigated. We investigated the modulation of symbiotic nitrogen fixation in soybean [Glycine max (L.) Merrill] at different plant densities. A field trial was performed in southern Brazil with six treatments, including non-inoculated controls without and with N-fertilizer, both at a density of 320,000 plants ha−1, and plants inoculated with Bradyrhizobium elkanii at four densities, ranging from 40,000 to 320,000 plants ha−1. Differences in nodulation, biomass production, N accumulation and partition were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glycine max; Biological nitrogen fixation; Photosynthesis; Source/sink manipulation; Plant density.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162014000300002

Magnesium-induced alterations in the photosynthetic performance and resistance of rice plants infected with Bipolaris oryzae
Provedor de dados: 63
Autores: Moreira,Wiler Ribas; Bispo,Wilka Messner da Silva; Rios,Jonas Alberto; Debona,Daniel; Nascimento,Clístenes Williams Araújo; Rodrigues,Fabrício Ávila.
Brown spot (BS), caused by the fungus Bipolaris oryzae, is one of the most important diseases contracted by rice. We investigated the effect of magnesium (Mg) on the development of BS, caused by Bipolaris oryzae, and the effects of disease development on the photosynthetic performance of rice (Oryza sativa L.) plants (cv. Metica-1) grown in nutrient solutions containing 0.25 or 4.0 mM of Mg. Assessments of BS severity, leaf Mg and pigment concentrations (total chlorophylls and carotenoids), were carried out at 120 h after inoculation, in addition to gas exchange parameters,. Higher leaf concentration of Mg was observed in plants supplied with 4.0 mM Mg than in those supplied with 0.25 mM. The increase in leaf Mg was accompanied by a decrease in BS...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oryza sativa; Foliar disease; Macronutrient; Photosynthesis; Plant nutrition.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162015000400328

Jatropha curcasand Ricinus communisdisplay contrasting photosynthetic mechanisms in response to environmental conditions
Provedor de dados: 63
Autores: Lima Neto,Milton Costa; Martins,Marcio de Oliveira; Ferreira-Silva,Sérgio Luiz; Silveira,Joaquim Albenísio Gomes.
Higher plants display different adaptive strategies in photosynthesis to cope with abiotic stress. In this study, photosynthetic mechanisms and water relationships displayed byJatropha curcasL. (physic nuts) andRicinus communisL. (castor bean), in response to variations in environmental conditions, were assessed.R. communis showed higher CO2 assimilation, stomatal and mesophyll conductance thanJ. curcas as light intensity and intercellular CO2 pressure increased. On the other hand,R. communis was less effective in stomatal control in response to adverse environmental factors such as high temperature, water deficit and vapor pressure deficit, indicating lower water use efficiency. Conversely,J. curcas exhibited higher photosynthetic efficiency (gas exchange...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Abiotic stress; Castor bean; Photosynthesis; Physic nut; Acclimation.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162015000300260

ผลของบราสสิโนสเตียรอยด์ต่อการสังเคราะห์ด้วยแสงและผลผลิตของข้าวพันธุ์ปทุมธานี 1 ภายใต้ภาวะเครียดจากความร้อน
Provedor de dados: 106
Autores: Kanapol Juthamanee; Jutiporn Thassakulpanit; Verasilp Sornsomboon; Lilly Kaweeta; Vitit Jaiaree; Apichart Sooksamrarn.
Brassinosteroids are the plant hormone reported to alleviate heat stress. This study investigated the response of rice (Oryza sativa L.cv. Pathum Thani 1) to 24-epibrassinolide (EBR) or 7,8-dihydro-8-20-hydroxyecdysone (DHECD) under high temperature by examine photosynthesis performance and yield. The results show that foliar application of 0.01 μM EBR and 0.1 μM DHECD on V7 vegetative growth could increase the photosynthetic efficiency under 40/30 ºC (day/night temperature). In field growth experiment, the application of those brassinosteroids concentrations on V7 growth stage could increase seed setting in all panicle part and number of normal seeds per particle. The results indicated that EBR and DHECD alleviated heat stress of rice ‘Pathum Thani 1’ by...
Tipo: Collection
Palavras-chave: Rice; Photosynthesis; Brassinosteroids; Yield; Heat stress; ข้าว; การสังเคราะห์แสง; ผลผลิต; บราสสิโนสเตียรอยด์; ความเครียดจากความร้อน; ฮอร์โมนพืช; การตอบสนองของพืช; การติดเมล็ด; พันธุ์ปทุมธานี 1.
Ano: 2012
URL: http://anchan.lib.ku.ac.th/agnet/handle/001/5326

ผลของการไม่ไถพรวนและการใช้วัสดุอินทรีย์ต่อการเจริญเติบโต ผลผลิตและการสังเคราะห์ด้วยแสงของข้าวในสภาพดินเค็ม
Provedor de dados: 106
Autores: Konkanok Phoudpho; Supasith Sithapanich; Wimonan Kanket; Pornthip Srimongkol; Chalermpol Kerdmani.
Tipo: Collection
Palavras-chave: Rice; Photosynthesis; Saline soil; Organic materials; Tillage; ข้าว; การสังเคราะห์แสง; ดินเค็ม; วัสดุอินทรีย์; การไถพรวน; การเจริญเติบโต; ผลผลิต.
Ano: 2012
URL: http://anchan.lib.ku.ac.th/agnet/handle/001/5368

การเปลี่ยนแปลงของการสังเคราะห์ด้วยแสงสุทธิ การคายน้ำ การเปิดปากใบ และประสิทธิภาพการใช้น้ำในกระบวนการสังเคราะห์ด้วยแสง ของกิ่งยางพาราสายพันธุ์ RRIM 600 ที่ถูกตัด
Provedor de dados: 106
Autores: Auntiporn Keansua; Sukumaporn Sriphadet; Jessada Phattaralerphong.
A study on changes in net photosynthesis (Pn), transpiration (Tr), stomatal conductance (Gs) and photosynthesis water use efficiency (WUE) of cutted rubber branch c.v. RRIM 600. Four methods included, do not put into the water, immediately put the branch into the water after cut, and put into the water after cut 5 and 10 minutes. The comparing of Pn, Tr, Gs and WUE values before and after cut were done. The result were found that Pn, Tr and Gs decrease immediately after branch was cut. The value decreased rapidly in first 15 minutes. Putting the branch into the water immediately, and putting the brance into the water 5 or and 10 minutes after cut expressed that the Pn, Tr, Gs and WUE could restored to the normal value before the branch was cut....
Tipo: PhysicalObject
Palavras-chave: Rubber; Cutted rubber branch; RRIM 600; Photosynthesis; Transpiration; Stomatal conductance; Water use efficiency; Plant physiology analysis; ยางพารา; กิ่งยางพารา; การสังเคราะห์ด้วยแสง; การตอบสนองต่อแสง; การเปิดปากใบ; การคายน้ำ; ประสิทธิภาพการใช้น้ำ; การวิเคราะห์สรีรวิทยาของพืช.
Ano: 2014
URL: http://anchan.lib.ku.ac.th/agnet/handle/001/5755

ผลของวัสดุอินทรีย์และระบบการไม่ไถพรวนต่อการเปลี่ยนแปลงสมบัติทางเคมีของดินในนาข้าว
Provedor de dados: 106
Autores: Puthipol Sirimool; Wimonan Kanket; Pornthip Srimongkol; Supasith Sithapanich.
Thailand is a country located on the tropical agriculture. Natural soil fertility is low. Low organic matter content. Due to the rapid degradation of the heat and humidity. Therefore,the concept adding of organic material and reduced tillage to improve soil properties for the better. The study on the effects of tillage systems on changes in soil chemical properties of rice. The experimental design was Randomize Complete Block Design (RCBD) 5 treatments. 1) tillage (control) 2) tillage with sunnhemp incorporation 3) tillage with rice straw incorporation 4) no tillage with sunn hemp mulching 5) no tillage with rice straw mulching. Soil samples were collected during the period, before transplant and 2 weeks after harvest. The soil reaction, electrical...
Tipo: PhysicalObject
Palavras-chave: Rice; Saline soil; Photosynthesis; Organic materials; Tillage; ข้าว; ดินเค็ม; การสังเคราะห์แสง; วัสดุอินทรีย์; การไถพรวน; การเจริญเติบโต; ผลผลิต.
Ano: 2012
URL: http://anchan.lib.ku.ac.th/agnet/handle/001/5449

Effect of environment on photosynthesis by corn
Provedor de dados: 106
Autores: Musgrave, R.B.
6 ill.
Palavras-chave: Corn; Maize; Photosynthesis; Environment; Growth rate; ข้าวโพด; การสังเคราะห์แสง; อัตราการเจริญเติบโต.
Ano: 1964
URL: http://anchan.lib.ku.ac.th/agnet/handle/001/3743

การตอบสนองของพันธุ์ข้าวไทยต่อระบบนาน้ำน้อย
Provedor de dados: 106
Autores: Nednapa Insalud; Supasit Sitthapanit; Jessada Phattaralerpong; Benjavan Rerkasem.
The development of a water saving rice growing system was stemmed from an attempt to manage efficient water usage, whereby reducing level of water use but still maintaining acceptable level of yield. To be successful in implementing the water saving rice growing system, it is necessary to understand a suitable photosynthetic mechanism and photosynthetic efficiency of each rice cultivar to be grown in such system. An understanding of such knowledge will lead to a better selection of healthy and high yielding cultivars. As such, this study was aimed to compare responses of 10 Thai rice cultivars in terms of photosynthesis rate and growth in well-drained and water-logged systems. Our data indicated that almost all rice cultivars grown under either...
Tipo: Collection
Palavras-chave: Plant growth; Photo response; Photosynthesis; Rice; Water management; Water saving system; ข้าว; การตอบสนองต่อแสง; การสังเคราะห์แสง; การเจริญเติบโต; การจัดการน้ำ; ระบบนาน้ำน้อย.
Ano: 2012
URL: http://anchan.lib.ku.ac.th/agnet/handle/001/5378

ผลของการใช้วัสดุอินทรีย์ต่อการตอบสนองของข้าวในดินเค็ม
Provedor de dados: 106
Autores: Konkanok Paopo; Porntip Srimongkol; Suphasit Sitthaphanit; Wimolnan Kanket.
Rice growth and yield are adversely affected by soil salinity. The application of organic matter is a successful technique for saline soil remediation. The experiment was conducted to determine the effect of different organic materials on the response of rice in saline soil. Experimental design was a randomized complete block with 4 replicates comprised 4 treatments: 1) no organic material application (control) 2) sesbania application at the rate of 1,000 kg/rai 3) rice straw application at the rate of 1,000 kg/rai and 4) sesbania at the rate of 500 kg/rai and rice straw at the rate of 500 kg/rai. The result were shown that sesbania and rice straw treatment had the highest rice dry weight in all growth stages, the highest nutrient uptake at booting stage,...
Tipo: PhysicalObject
Palavras-chave: Rice; Sesbania; Rice straw; Organic material; Saline soil; Soil management; Soil amendments; Organic material application; Photosynthesis; Yield; Plant response; Rice production; ข้าว; โสนอัฟริกัน; ฟางข้าว; วัสดุอินทรีย์; ดินเค็ม; การจัดการดิน; การปรับปรุงดิน; การตอบสนองของพืช; การสังเคราะห์แสง; อัตราผลผลิต; การผลิตข้าว.
Ano: 2014
URL: http://anchan.lib.ku.ac.th/agnet/handle/001/5754

Hydrogen peroxide reduces sensitivity to aluminum in canola?
Provedor de dados: 109
Autores: Quintão Scalon,Silvana de Paula.
Abstract The objective of this study was to evalúate the effect of aluminum and the mitigating potential of H2O2 on the stress and antioxidant responses in canola (Brassica napus var. oleifera (Moench) Delile) affecting the emergence and initial growth of plants. Canola seeds, cultivar Hyola 61, were treated with different concentrations of H2O2 solution (0.0, 0.075, and 0.15 M), and later sown under different concentrations of aluminum (0.0, 10, 20, and 30 mmolc dm-3). After 20 days of plant emergence, survival and growth characteristics were evaluated. 20, 30, 40, 50, and 60 days after emergence, height, chlorophyll index, chlorophyll a fluorescence, and the activity of superoxide dismutase in the roots were determined. The canola is sensitive to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chlorophyll a fluorescence; Oilseed; Photosynthesis; Stress.
Ano: 2021
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122021000200141

Effect of soil water availability on gas exchange in young trees of Eucalyptus grandis W. Hill ex Maiden
Provedor de dados: 109
Autores: Mejía-de Tafur,María Sara; Riaño-Herrera,Néstor Miguel; Urrego-Mesa,John Byron; Ibarra-Espinosa,Dora Mónica; Zapata-Duque,Claudia Marcela.
Abstract Two outdoor trials were conducted in the department of Valle del Cauca, Colombia, in contrasting climatic conditions, to evaluate the effect of soil water availability on the gas exchange of four elite genotypes of Eucalyptus grandis as follows: 28-3, 18-3, 24A-5 and 19-1, respectively. One trial was conducted on the campus of the Universidad Nacional de Colombia located in Palmira, at 994 m.a.s.l. with an average temperature of 23.5°C (maximum of 31°C, minimum of 18°C), and 76% relative humidity (RH). The second trial was conducted at the nursery of Carton de Colombia S.A., located in Restrepo, at 1450 m.a.s.l. with an average temperature 18°C (maximum of 26°C, minimum of 12°C) and 80% RH. A split-plot design with four replicates was used....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Water stress; Waterlogging; Stomatal conductance; Photosynthesis; Transpiration.
Ano: 2017
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122017000400549

Differential response of photosynthetic activity, leaf nutrient content and yield to long-term drought in cacao clones
Provedor de dados: 109
Autores: Jaimez,Ramón; Loor,Rey; Arteaga,Francisco; Márquez,Víctor; Tezara,Wilmer.
Abstract Cacao (Theobroma cacao L.) is not frequently cropped in water limited environments, however it is cultivated in several drought-prone regions, where soil water is gradually depleted on an annual cycle. In regions where cacao is subjected to long periods without precipitation, the physiological responses under field conditions may differ between cacao clones. Evaluation of these responses are required to select potential clones that could be used for breeding programs in the context of future climatic scenarios. In order to identify physiological and yield responses to drought of 10 Ecuadorian cacao clones, relative leaf water content (RWC), CO2 assimilation rate (A), transpiration (E), stomatal conductance (gs), water use efficiency (WUE),...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cacao; Chlorophyll fluorescence; Photochemical protection; Photosynthesis; Water deficit.
Ano: 2021
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122021000300274

Photosynthetic parameters and growth in seedlings of Bertholletia excelsa and Carapa guianensis in response to pre-acclimation to full sunlight and mild water stress
Provedor de dados: 36
Autores: Azevedo,Gracilene Fernandes da Costa.
Light and water are important factors that may limit the growth and development of higher plants. The aim of this study was to evaluate photosynthetic parameters and growth in seedlings of Bertholletia excelsa and Carapa guianensis in response to pre-acclimation to full sunlight and mild water stress. I used six independent pre-acclimation treatments (0, 90 (11h15-12h45), 180 (10h30-13h30), 360 (09h00-15h00), 540 (07h30-16h30) and 720 min (06h00-18h00)) varying the time of exposure to full sunlight (PFS) during 30 days, followed by whole-day outdoor exposure for 120 days. Before PFS, the plants were kept in a greenhouse at low light levels (0.8 mol m-2 day-1). The PFS of 0 min corresponded to plants constantly kept under greenhouse conditions. From the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazonia; Forest tree species; Photosynthesis; Stomatal conductance.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672014000100007

PHOTOSYNTHETIC PERFORMANCE AND LEAF WATER POTENTIAL OF GULUPA (Passiflora edulis Sims, PASSIFLORACEAE) IN THE REPRODUCTIVE PHASE IN THREE LOCATIONS IN THE COLOMBIAN ANDES
Provedor de dados: 37
Autores: PEREZ MARTINEZ,Laura Victoria; MELGAREJO,Luz Marina.
Gulupa, Passiflora edulis Sims (Passifloraceae), is an important fruit due to its organoleptic and nutritional characteristics and its demand in the international market; however, very few studies have been conducted for studying its Ecophysiology. Until now, this crop has spread throughout the country through empirical knowledge without data that indicate the zones that are more suitable for its cultivation. For this reason, gas exchange, chlorophyll fluorescence (photosystem II operating efficiency and maximum quantum efficiency of photosystem II photochemistry) and leaf water potential were measured in three different locations of Cundinamarca department (Chia [2610 m a.s.l., 14 °C], Granada [2230 m a.s.l., 15 °C] and Tena [2090 m a.s.l., 17 °C]), whose...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chlorophyll fluorescence; Crop; Horticulture; Passion fruit; Photosynthesis; Plant physiology; Water.
Ano: 2015
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-548X2015000100019

EFFECTS OF FUNGICIDES ON ENDOPHYTIC FUNGI AND PHOTOSYNTHESIS IN SEEDLINGS OF A TROPICAL TREE, Guarea guidonia (Meliaceae)
Provedor de dados: 37
Autores: GAMBOA GAITÁN,MIGUEL A.; WEN,SHIYUN; FETCHER,NED; BAYMAN,PAUL.
Endophytes are microorganisms that live within healthy plant tissues, and include fungi and bacteria. They can be mutualists, comensals or even latent pathogens. Presence of these endosymbionts may affect host physiology, for example by consuming products of photosynthesis (endophytes are heterotrophs) or producing toxic metabolites. In this work two fungicides were used to eliminate fungal endophytes from seedlings of Guarea guidonia. Lightsaturated photosynthesis (Amax) was measured in endophytefree plants and compared with control plants. Each fungicide killed different fungal endosymbionts. Phomopsis was more susceptible to benomyl while Colletotrichum was more susceptible to propiconazole. Although suggestive, values of Amax were not significantly...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Endophytes; Tropics; Photosynthesis; Fungicides; Guarea.
Ano: 2005
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-548X2005000200003

Photosynthetic characteristics of the freshwater red alga Batrachospermum delicatulum (Skuja) Necchi &amp;amp; Entwisle
Provedor de dados: 39
Autores: Necchi Júnior,Orlando; Alves,Abner H.S.
Six populations of the freshwater red alga Batrachospermum delicatulum (Skuja) Necchi &amp;amp; Entwisle, including gametophyte and 'Chantransia' stage, were analysed in culture and natural conditions applying chlorophyll fluorescence and oxygen evolution. Parameters derived from the photosynthesis-irradiance curves indicated adaptation to low irradiance for all populations, which was characterized by photoinhibition, low values of Ik and Ic and high values of a. Data from both techniques revealed significant differences among populations and phases for most photosynthetic parameters. Similarly, photosynthesis responded differently to variations in temperature in each population with similar rates under a wide range of temperature. No consistent pattern...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Batrachospermum; Photosynthesis; Irradiance; PH; Diurnal rhythm; Temperature.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062005000100012

Growth and carbon assimilation limitations in Ricinus communis (Euphorbiaceae) under soil water stress conditions
Provedor de dados: 39
Autores: Sausen,Tanise Luisa; Rosa,Luís Mauro Gonçalves.
Water availability may influence plant carbon gain and growth, with large impacts on plant yield. Ricinus communis (L.), a drought resistant species, is a crop with increasing economic importance in Brazil, due to its use in chemical industry and for the production of biofuels. Some of the mechanisms involved in this drought resistance were analyzed in this study by imposing progressive water stress to pot-grown plants under glasshouse conditions. Water withholding for 53 days decreased soil water gravimetric content and the leaf water potential. Plant growth was negatively and significantly reduced by increasing soil water deficits. With irrigation suspension, carbon assimilation and transpiration were reduced and remained mostly constant throughout the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: A/Ci curves; Diurnal changes; Photosynthesis; Stomatal limitations; Water stress.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062010000300008

Freeze tolerance differs between two ecotypes of Paspalum vaginatum (Poaceae)
Provedor de dados: 39
Autores: Fabbri,Liliana Teresa; Ploschuk,Edmundo Leonardo; López,María Virginia; Insausti,Pedro; Rua,Gabriel Hugo.
Morphological and physiological responses to freezing were evaluated in two ecotypes of the perennial turfgrass Paspalum vaginatum. Leaf extension rate, number of active meristems, leaf water potential and net photosynthesis were measured on plants of both a commercial cultivar, 'Sea Isle 2000', and a wild ecotype from the Flooding Pampa grasslands of Argentina. Plants were propagated by cloning, cultivated in pots, and examined during 18 consecutive days under two treatments: a non-frozen control treatment (15.5±7 ºC) and a frozen treatment with two stages: Stage 1 with four hours of freezing stress for 10 nights (-5ºC), and Stage 2 with 12 hours of freezing stress for eight nights (five nights at -5ºC and three nights at -8ºC). After these treatments,...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Freezing tolerance; Leaf water potential; Meristem injury; Paspalum vaginatum; Photosynthesis; Seashore paspalum; Turfgrass.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062016000100152

Increased atmospheric CO2 changes the photosynthetic responses of Acrocomia aculeata (Arecaceae) to drought
Provedor de dados: 39
Autores: Rosa,Bruno Luan; Souza,João Paulo; Pereira,Eduardo Gusmão.
ABSTRACT Water availability is the main factor that explains current patterns of palm abundance. However, the interaction between water stress and increasing atmospheric CO2 concentrations caused by climatic change and its effects on palm physiology remain poorly known. Macauba palm is a widespread Neotropical species commonly found in ecosystems subjected to seasonal drought and has potential use in oil production. The present work investigated the influence of increased CO2 concentrations on photosynthetic responses to drought in macauba palm plants. Exposure to increased CO2 concentrations led to up-regulation of photosynthesis through higher stomatal conductance and improved light and water use efficiency. Macauba palm plants under water stress,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Climate change; Photosynthesis; Palm; Water stress; Water use efficiency.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062019000300486

Synergy between cadmium and zinc in bean plants cultivated in multi contaminated soils
Provedor de dados: 1
Autores: Almeida, Lorena Gabriela; Silva, Dayane Meireles da; Jorge, Adelcio de Paula; Souza, Kamila Rezende Dázio de; Guilherme, Luiz Roberto Guimarães; Alves, José Donizeti.
Agricultural species are subjected to a variety of biotic and abiotic stresses, which are the main limitations to crop production. In this context, contamination by trace elements is characterized as an abiotic stress that represents an environmental problem. Due to the physical and chemical similarities between cadmium and zinc, these elements may interact in the environment and may cause antagonistic or synergistic effects. In this way, physiological mechanisms to exclude, detoxify or compartmentalize trace elements that are in excess are crucial for plant survival when exposed to high concentrations of these elements. In this way, the aim of this study was to understand the physiological responses of Phaseolus vulgaris plants subjected to increasing...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Trace elements; Antioxidante enzymes; ROS; Photosynthesis; Synergism. Fisiologia Vegetal.
Ano: 2018
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/35829

Gas exchange of potted Tabebuia aurea plants under hydric stress - doi: 10.4025/actasciagron.v33i4.11254
Provedor de dados: 1
Autores: Oliveira, Ademir Kleber Morbeck; Universidade Anhanguera; Gualtieri, Sônia Cristina Juliano de; Universidade Federal de São Carlos; Bocchese, Ricardo Anghinoni; Universidade Anhanguera.
To evaluate the effects of hydric stress on CO2 and H2O exchange, five-month-old Tabebuia aurea seedlings cultivated in planting bags were subjected to hydric stress by suppressing irrigation for 21 days. After 14 days without irrigation, the rates of transpiration, stomatal conductance and net photosynthesis in leaves were zero, while the hydric potential of leaves reached -2.4 MPa. After this point, daily irrigation was resumed, and the values of the measured variables recovered to initial levels after 96 hours (transpiration rate from 3.2 to 3.5 mmol m-2 s-1; stomatal conductance rate from 0.32 to 0.35 mol m-2 s-1 and photosynthesis rate from 8.0 to 9.8 &amp;micro;mol m-2 s-1). Likewise, hydric potential values were similar to those at the beginning of...
Palavras-chave: 5.02.01.06-9 hydric deficit; Photosynthesis; Conductance; Tabebuia Fisiologia Florestal hydric deficit; Photosynthesis; Conductance; Tabebuia.
Ano: 2011
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/11254

Synergy between cadmium and zinc in bean plants cultivated in multi contaminated soils
Provedor de dados: 1
Autores: Almeida, Lorena Gabriela; Silva, Dayane Meireles da; Jorge, Adelcio de Paula; Souza, Kamila Rezende Dázio de; Guilherme, Luiz Roberto Guimarães; Alves, José Donizeti.
Agricultural species are subjected to a variety of biotic and abiotic stresses, which are the main limitations to crop production. In this context, contamination by trace elements is characterized as an abiotic stress that represents an environmental problem. Due to the physical and chemical similarities between cadmium and zinc, these elements may interact in the environment and may cause antagonistic or synergistic effects. In this way, physiological mechanisms to exclude, detoxify or compartmentalize trace elements that are in excess are crucial for plant survival when exposed to high concentrations of these elements. In this way, the aim of this study was to understand the physiological responses of Phaseolus vulgaris plants subjected to increasing...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Trace elements; Antioxidante enzymes; ROS; Photosynthesis; Synergism.; Fisiologia Vegetal.
Ano: 2018
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/35829

Photosynthetic pigments and gas exchange in castor bean under conditions of above the optimal temperature and high CO2
Provedor de dados: 1
Autores: Silva, Fabiola França; Mendes, Bruna Silva; Rocha, Maria Socorro; Brito Neto, José Félix; Beltrão, Napoleão Macêdo; Sofiatti, Valdinei.
The castor bean plant, a Euphorbiaceae oil seed C3-metabolism rustic and drought-resistant plant, is cultivated in a wide range of environments due to its good adaptive capacity. However, given the current environmental changes, many biochemical and physiological impacts may affect the productivity of important crops, such as castor bean. This work aimed to evaluate the impacts of the castor bean gas exchange in response to high temperature and increased CO2concentration.Our experiment was conducted in a phytotron located at Embrapa Algodão in 2010. We adopted a completely randomized design, with four treatments in a factorial combination of two temperatures (30/20 and 37/30°C) and two CO2 levels (400 and 800 mmol L-1); four replications were performed,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: 5.01.03.00-8 castor bean; Climate change; Gas exchange; Photosynthesis; Chlorophyllssíntese  clorofila 5.01.03.06-7.
Ano: 2015
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/19075

Influência da queima no teor de pigmentos, proteína solúvel e carboidratos em gramíneas de pastagens naturais - doi: 10.4025/actascianimsci.v32i3.8400
Provedor de dados: 2
Autores: Mendes, Cristina Rodrigues; UFSM; Lima, Maria da Graça de Souza; UFPel; Quadros, Fernando Luiz Ferreira de; UFSM; Abreu, Claudete Miranda; FURG; Garagorry, Fábio Cervo; UFSM.
A importância do fogo na origem e na manutenção das áreas de pastagens é bastante discutida. O objetivo foi verificar a influência da queima no teor de pigmentos fotossintéticos, proteína solúvel e carboidratos em gramíneas nativas de pastagem sob pastoreio rotacionado. Foram avaliadas as lâminas foliares de oito gramíneas, de pastagem natural, representantes de quatro grupos funcionais. Foram quantificados teores de pigmentos, proteínas solúveis, carboidratos solúveis, amido e açúcares redutores. A maioria das espécies sem queima teve maior teor de pigmentos. De modo geral, não houve efeito do fogo sobre a proteína solúvel, porém as espécies D. sabulorum, A. affinis e A. laevis se destacaram como o grupo de maior teor proteico solúvel dentre as espécies...
Palavras-chave: Carotenóide; Clorofila; Fotossíntese; Fogo; Grupos funcionais Carotenoid; Chlorophyll; Photosynthesis; Fire; Functional groups.
Ano: 2010
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAnimSci/article/view/8400

Características fotossintéticas de genótipos de capim-elefante anão (Pennisetum purpureum Schum.), em estresse hídrico - DOI: 10.4025/actascianimsci.v32i1.8961
Provedor de dados: 2
Autores: Araújo, Saulo Alberto do Carmo; UFVJM; Vasquez, Hernan Maldonado; UENF; Campostrini, Eliemar; UENF; Netto, Alena Torres; UENF; Deminicis, Bruno Borges; UENF; Lima, Érico da Silva; UENF.
O experimento foi realizado com o objetivo de avaliar as trocas gasosas de genótipos de capim-elefante anão, em diferentes condições hídricas. O delineamento experimental foi inteiramente casualizado com três repetições. Foram avaliados três genótipos de capim-elefante anão (Mott, CNPGL 94-34-3 e CNPGL 92-198-7) em duas condições de umidade do solo: irrigado (I) e não-irrigado (NI). Foi observada diferença entre os tratamentos I e NI para todos os genótipos em relação à taxa fotossintética, condutância estomática, transpiração e déficit de pressão de vapor. O genótipo CNPGL 94-34-3 apresentou maior tolerância ao estresse hídrico, seguido pelos genótipos Mott e CNPGL 92-198-7. Todos os genótipos avaliados apresentaram, em condições ideais de umidade do...
Tipo: Pesquisa de campo
Palavras-chave: Ciências Agrárias condutância estomática; Déficit de pressão de vapor; Fotoinibição; Fotossíntese; Transpiração Zootecnia stomatal conductance; Vapor pressure deficit; Photoinhibition; Photosynthesis; Transpiration.
Ano: 2009
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAnimSci/article/view/8961

Lanthanum content and effects on growth, gas exchanges, and chlorophyll index in maize plants
Provedor de dados: 3
Autores: Duarte, Ana Carolina Oliveira; Oliveira, Cynthia de; Ramos, Sílvio Júnio; Castro, Evaristo Mauro de; Siqueira, José Oswaldo; Guilherme, Luiz Roberto Guimarães.
Rare earth elements, such as lanthanum (La), have been applied to agriculture via fertilizers, aiming to increase the productivity and crop quality, such results observed mainly in China. However, the knowledge about the effect of La on maize growth, as well as for other species, despite the growing interest it is still limited. The aim of this study was to evaluate the effects of La on maize growth, La content, photosynthetic rate and chlorophyll content in maize plants in response to La treatment (0, 25, 50, 100, 150, 300 and 600 μM) in nutrient solution for three weeks. The plants were placed in geminated pots using a split-root technique. One of the pots in the geminated set was filled with a complete nutrient solution without La, while another was...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ciências Agrárias crops; Photosynthesis; Rare earth elements; Zea mays. Produção Vegetal.
Ano: 2018
URL: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/38469

The optimum design of the air-conditioning system of a plant factory with a high-efficient water use and the effect of its higher humidity condition on growth in plants
Provedor de dados: 111
Autores: Matsuo, Seiji.
The authors designed the optimal air-conditioning system of the greenhouse which minimizes the water and energy by computer simulation. In this design, a heat balance model and water balance model in the green house were constructed and they were considered to be constrained conditions. Furthermore, in order to evaluate the influence of the plant on this condition, the effect of higher relative humidity levels on the growth chambers of cucumber seedlings were also investigated. Three higher relative humidity conditions, RH74.5%, 86% and 97.8%, were taken into consideration in the experiment. Consequently, it was useful to introduce the fog cooling system, thermal storage mediums, ice from the desalination process and gas absorption refrigerator with...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: High-efficient water; Energy-saving; Optimal design; Temperature and humidity adjustment; Environmental control; Photosynthesis.
Ano: 2015
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3062

Photosynthetic characteristics and growth of alginate-immobilized Scenedesmus obliquus
Provedor de dados: 115
Autores: Ruiz-Marín,Alejandro; Mendoza-Espinosa,Leopoldo G.; Sánchez-Saavedra,M. del P.
The micfoalgae Scenedesmus obliquus was immobilized in Ca-alginate beads at two stocking cell densities (6.7 X10(5) and 1.5X 10(6) cell bead-1). The photosynthetic fate (P), the initial slope of the photosynthesis (α), and the threshold fot irradiance-saturated photosynthesis (Ek) were determined; later, the growth and protein content for S. obliquus immobilized in beads-alginate under two light intensities (135 and 200 μE m -2 s -1) was evaluated using stocking cell densities that had previously presented the largest photosynthetic rate. Results showed than photosynthetic rates (P) and α of cells immobilized in beads at low stocking density (0.14 μmol O2 h-1 10-6 cells and 0.00056) were greater than in beads with high stocking density (0.02 μmol O2 h-1...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Scenedesmus obliquus; Photosynthesis; Immobilized cells protein content.
Ano: 2011
URL: http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S1405-31952011000300004

Effects of water deficit on gas exchange of different age leaves and both stem and leaves solute content of sunflowers
Provedor de dados: 115
Autores: Canavar,Öner.
Water deficit alters biochemical and physiological processes ranging from photosynthesis to protein synthesis and solute accumulation in the different organs of the plant. The objectives of this study were to determine the effect of water deficit on photosynthetic responses of leaves at different ages and the accumulation of soluble sugar and starch in the stems and leaves of sunflowers (Helianthus annuus L.). Two sunflower cultivars (Sanbro and TR-3080) were used under two water regimes, well watered (70 % irrigation) and water deficit (20 % irrigation) according to the field capacity of soil under greenhouse conditions. The experimental design was randomized complete block with five replicates. The transpiration rate (E), the ratio of intercellular air...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Helianthus annuus L.; Photosynthesis; Stomatal limitation; Water deficit.
Ano: 2015
URL: http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S1405-31952015000600005

A new concept for insect damage evaluation based on plant physiological variables
Provedor de dados: 42
Autores: Neves,Ademir D.; Oliveira,Ricardo F.; Parra,José R.P.
The objective of this study was to determine the damage levels caused by Orthezia praelonga Douglas, 1891 and Leucoptera coffeella (Guérin-Mèneville 1842), on rangpur lime and Obatã coffee leaves, respectively. Measurements were based on a new concept for the evaluation of the following plant physiological parameters: photosynthesis, stomatal conductance, leaf temperature and transpiration, and internal concentration of CO2 (by infrared analyzer). A negative correlation between infestation level and photosynthesis was found, where the negative inflexion point of the curve was considered as a reference for damage levels. The control level for O. praelonga is below the 7-13% limit for damaged leaf area (40 to 70 scales per leaf), while for L. coffeella it is...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Economic level injury; Citrus; Coffee; Plant-insect interactions.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652006000400015

Copper Stress on Photosynthesis of Black Mangle (Avicennia germinans)
Provedor de dados: 42
Autores: GONZALEZ-MENDOZA,DANIEL; GIL,FRANCISCO ESPADAS y; ESCOBOZA-GARCIA,FERNANDO; SANTAMARIA,JORGE M.; ZAPATA-PEREZ,OMAR.
The effects of copper toxicity on the photosynthetic activities of Avicennia germinans was investigated using two CuSO4 concentrations (0.062 and 0.33 M) added in Hoagland's solution in an aerated hydroponic system. Photosynthesis and chlorophyll fluorescence were measured after 30 h of copper stress. Results obtained in this study show that increasing levels of Cu+2 of 0.062 and 0.33 M Cu+2 resulted in a general reduction of the stomatal conductance (28 and 18%, respectively) and 100% of inhibition of net photosynthesis. Additionally, at these concentrations of Cu+2, reductions of chlorophyll fluorescence parameters were also observed. These changes suggested that the photosynthetic apparatus of Avicennia germinans was the primary target of the Cu+2...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Avicennia germinans; Chlorophyll fluorescence; Copper; Photosystem II; Photosynthesis.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652013000200665

Physiological responses of soybean (Glycine max (L.) Merrill) cultivars to copper excess
Provedor de dados: 42
Autores: SCHWALBERT,RAISSA; SILVA,LINCON O.S.; SCHWALBERT,RAI A.; TAROUCO,CAMILA P.; FERNANDES,GILLIAN S.; MARQUES,ANDERSON C.R.; COSTA,CAMILA C.; HAMMERSCHMITT,RODRIGO K.; BRUNETTO,GUSTAVO; NICOLOSO,FERNANDO T.
Abstract Abstract: Successive applications of copper fungicides on vines have resulted in increased copper content in vineyard soils over the years. This high copper content has affected the growth of young vines in eradicated vineyards. Thus, the cultivation of annual species for a few years is an alternative to copper phytostabilization, because it would be a good way to decrease copper availability to plants. The aim of this study was to evaluate the physiological responses of different soybean cultivars to copper concentration increase. Four different soybean cultivars were grown under three copper concentrations: 0.5, 20 and 40 μM in nutrient solution. The main outcomes of this study were: i) Cultivar M 6410 IPRO recorded the highest photosynthetic...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antioxidant system; Cash crops; Heavy metal phytostabilization; Photosynthesis.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652019000700618

Gas exchange and antioxidant activity in seedlings of C opaifera langsdorffii Desf. under different water conditions
Provedor de dados: 42
Autores: ROSA,DEREK B.C.J.; SCALON,SILVANA P.Q.; CREMON,THAIS; CECCON,FELIPE; DRESCH,DAIANE M.
ABSTRACT The aim of this study was to evaluate gas exchange, efficiency of the photosynthetic apparatus, and antioxidant activity in Copaifera langsdorffii Desf. The seedlings were cultivated under different conditions of water availability, in order to improve the utilization efficiency of available water resources. The seedlings were cultivated in four different water retention capacities (WRC- 25%, 50%, 75%, and 100%), and evaluated at four different time (T- 30, 60, 90, and 120 days). During the experimental period, seedlings presented the highest values for carboxylation efficiency of Rubisco (A/Ci), intrinsic water use efficiency (IWUE = A/gs), chlorophyll index, and stomatal opening, when grown in the substrate with 75% WRC, but the stomatal index...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antioxidant enzymes; Chlorophyll a fluorescence; Photosynthesis; Water stress.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652017000603039

Carbon sequestration in the rain forest: alternatives using environmentally friendly biotechnology
Provedor de dados: 49
Autores: Buckeridge,Marcos S.; Aidar,Marcos P.M.
As carbon dioxide increases on Earth atmosphere, the rise in average temperatures may provoke changes in the environment that could damage civilisation as we know it. As a result, the need to sequester carbon becomes urgent, and one of the options we have is to use the potential of the forests to do it by enhancing assimilation of CO2 through photosynthesis. However, if we consider the use of plants to increase carbon sequestration, a problem that looms is that species often acclimate and actually reduce CO2 assimilation through feedback mechanisms of the sugars that are the product. In the present article, we propose that some biochemical pathways, such as those in control of photosynthesis, carbohydrate metabolism and assimilation, and cellulose and...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Global change; Carbon Sequestration; Photosynthesis; Rain Forest; Sugar Sensing; Cellulose synthesis; Gene therapy.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032002000100002

Measurements of CO2 exchange over a woodland savanna (Cerrado Sensu stricto) in southeast Brasil
Provedor de dados: 49
Autores: Rocha,Humberto R. da; Freitas,Helber C.; Rosolem,Rafael; Juárez,Robinson I.N.; Tannus,Rafael N.; Ligo,Marcos A.; Cabral,Osvaldo M. R.; Dias,Maria A.F. Silva.
The technique of eddy correlation was used to measure the net ecosystem exchange over a woodland savanna (Cerrado Sensu stricto) site (Gleba Pé de Gigante) in southeast Brazil. The data set included measurements of climatological variables and soil respiration using static soil chambers. Data were collected during the period from 10 October 2000 to 30 March 2002. Measured soil respiration showed average values of 4.8 molCO2 m-2s-1 year round. Its seasonal differences varied from 2 to 8 molCO2 m-2s-1 (Q10 = 4.9) during the dry (April to August) and wet season, respectively, and was concurrent with soil temperature and moisture variability. The net ecosystem CO2 flux (NEE) variability is controlled by solar radiation, temperature and air humidity on diel...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cerrado; Savanna; Photosynthesis; Soil respiration; Carbon sequestration; Eddy correlation.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032002000100009

Effect of atmospheric CO2 enrichment on the establishment of seedlings of Jatobá, Hymenaea Courbaril L. (Leguminosae, Caesalpinioideae)
Provedor de dados: 49
Autores: Aidar,M.P.M.; Martinez,C.A.; Costa,A.C.; Costa,P.M.F.; Dietrich,S.M.C.; Buckeridge,M.S.
Plants grown in elevated CO2 environments may exhibit photosynthetic acclimation or down regulation, which is characterised by reduced rates of photosynthesis. In most cases of CO2-induced photosynthetic acclimation, the reduced rates of photosynthesis were still higher than those detected in plants growing at ambient CO2 concentrations. In this work we present a study on the behaviour of seedlings of Hymenaea courbaril, a late secondary/climax species that is one of the most important trees in mature tropical forests of the Americas. After germination, the seedling of H. courbaril increases its rate of growth due to the mobilisation of massive amounts of a storage cell wall polysaccharide (xyloglucan) from its cotyledons. In our experiments, germinated...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; CO2 enrichment; Hymenaea courbaril; Storage mobilisation; Root:shoot ratio; Seedling growth; Cotyledons; Open top chamber; Xyloglucan; Biodiversity.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032002000100008

Source-sink relationships in two soybean cultivars with indeterminate growth under water deficit
Provedor de dados: 53
Autores: Silva,Alexandre José da; Magalhães Filho,José Rodrigues; Sales,Cristina Rodrigues Gabriel; Pires,Regina Célia de Matos; Machado,Eduardo Caruso.
Abstract Water deficit is a major factor limiting crop yield in rainfed areas. We hypothesized that under water deficit the decrease of photosynthetic production stimulates: carbohydrate remobilization from leaves, stems and roots to reproductive organs; and decreasing flowering intensity and pod development. The present work aims to study the effect of water deficit during bloom and grain pod-filling stages in two indeterminate soybean cultivar, Vtop and Nidera. The following physiological parameters were evaluated by means of daily CO2 assimilation rate (Ai), dynamic of carbohydrates in tissues, plant growth, grain yield and yield components. The study was conducted in a greenhouse with plants sown in tanks of 0.5 m3. Regardless of the phenological...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glycine max L. Merrill; Photosynthesis; Carbohydrate; Pod growth; Seed growth.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052018000100023

Endophytic bacteria affect sugarcane physiology without changing plant growth
Provedor de dados: 53
Autores: Marcos,Fernanda Castro Correia; Iório,Raquel de Paula Freitas; Silveira,Adriana Parada Dias da; Ribeiro,Rafael Vasconcelos; Machado,Eduardo Caruso; Lagôa,Ana Maria Magalhães de Andrade.
ABSTRACT The aim of this study was to evaluate if endophytic bacteria inoculants would be beneficial to the sugarcane varieties IACSP94-2094 and IACSP95-5000, promoting changes in photosynthesis and plant growth. The plants, obtained from mini stalks with one bud, were treated with two bacteria mixtures (inoculum I or II) or did not receive any inoculum (control plants). The inocula did not affect shoot and root dry matter accumulation as compared to the control condition (plants with native endophytic bacteria). However, photosynthesis and electron transport rate (ETR) increased in IACSP94-2094 treated with the inoculum II, whereas the inoculum I enhanced photosynthesis and stomatal conductance in IACSP95-5000. The inoculum II caused increase in leaf...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Saccharum spp.; Plant-bacteria interaction; Photosynthesis; Nitrogen; Mini stalks with one bud.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052016000100001

Morpho-physiological and mineral nutrient characterization of 45 collected Purslane (Portulaca oleracea L.) accessions
Provedor de dados: 53
Autores: Alam,Amirul; Juraimi,Abdul Shukor; Yusop,Mohd Rafii; Hamid,Azizah Abdul; Hakim,Abdul.
This study was carried out to determine, evaluation and characterization of the morphological, physiological as well as mineral nutrient vitiations among all forty five purslane accessions collected from different locations of West Peninsular, Malaysia. Significant differences (p&lt;0.05) were observed for all those traits measured regarding morphological, physiological and mineral composition. Morphological traits viz. plant height varied between 20.06-40.8 cm; number of main branch, 1.4-4.4; number of nodes, 8.4-31; internode distance, 2.1-3.43 cm; stem diameter, 2.12-3.8 mm; number of leaves, 97-1019; leaf area, 1.03-2.21 cm², number of flowers, 14-826.8; root length, 5.09-11.7 cm; fresh weight, 40-280 g; and dry weight varied between 2.71-29.16 g....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Purslane; Total chlorophyll; Photosynthesis; Stomatal conductance; Transpiration; Mineral composition.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052014000400011

Glyphosate-resistant hairy fleabane competition in RR® soybean
Provedor de dados: 53
Autores: Silva,Diecson Ruy Orsolin da; Vargas,Leandro; Agostinetto,Dirceu; Mariani,Franciele.
Weed competition in the soybean causes changes in morphological and physiological characteristics that reduce the competitive ability of the crop. The objective of this study was to determine the control periods and coexistence of glyphosate-resistant hairy fleabane and its interference in morphological and photosynthetic variables and RR soybean yield. A field experiment was conducted during the 2011/2012 growing season, the treatments consisted of weed interference and weed free periods of the glyphosate-resistant hairy fleabane with soybean (BRS Estância RR). The periods were 0, 7, 14, 21, 28, 35, 42 and 154 days after the soybean emergence. The results sugested no differences between the control periods for the variables evaluated. The increase...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glycine max; Weed interference; Photosynthesis.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052014000400014

Water deficiency at different developmental stages of Glycine max can improve drought tolerance
Provedor de dados: 53
Autores: Kron,Alan Panaia; Souza,Gustavo Maia; Ribeiro,Rafael Vasconcelos.
Developmental windows are specific periods of sensitivity during normal plant development in which a perturbation may be adaptively integrated. In these periods, sub-lethal environmental perturbations may improve the capacity to grow at lethal conditions. The aim of this study was to test the hypothesis that previous non-lethal water deficit applied in different developmental stages in soybean plants could enables them to improve the tolerance to environmental perturbations. In order to test this hypothesis we carried out an experiment with soybean plants submitted to water deficit in different stages of plant development, evaluating yield and physiological aspects. Our results indicated that water deficit experienced on V4 stage (vegetative) induces more...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Crop yield; Photosynthesis; Plant stress; Soybean.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052008000100005

Nitric oxide reduces oxidative damage induced by water stress in sunflower plants
Provedor de dados: 53
Autores: Cechin,Inês; Cardoso,Guilherme Sementili; Fumis,Terezinha de Fátima; Corniani,Natália.
Drought is one of the main environmental constraints that can reduce plant yield. Nitric oxide (NO) is a signal molecule involved in plant responses to several environmental stresses. The objective of this study was to investigate the cytoprotective effect of a single foliar application of 0, 1, 10 or 100 µM of the NO donor sodium nitroprusside (SNP) in sunflower plants under water stress. Water stressed plants treated with 1μM SNP showed an increase in the relative water content compared with 0 μM SNP. Drought reduced the shoot dry weight but SNP applications did not result in alleviation of drought effects. Neither drought nor water stress plus SNP applications altered the content of photosynthetic pigments. Stomatal conductance was reduced by drought...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Reactive oxygen species; Antioxidant enzymes; Proline; Malondialdehyde.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052015000200200

Photosynthetic response of soybean to twospotted spider mite (Acari: Tetranychydae) injury
Provedor de dados: 52
Autores: Bueno,Adeney de Freitas; Bueno,Regiane Cristina Oliveira de Freitas; Nabity,Paul David; Higley,Leon George; Fernandes,Odair Aparecido.
The twospotted spider mite Tetranychus urticae Koch is a common pest on soybean plants. To clarify plant-arthropod interaction on mite-soybean system, leaf fluorescence, photosynthetic responses to variable carbon dioxide levels, and chlorophyll content were evaluated. Significant photosynthetic rate reduction was observed due to stomatal limitation. Stomatal closure was the major plant physiological response. As a consequence, there was reduction in photosynthetic rates. Surprisingly, plants did not show chlorophyll content reduction associated with photosynthetic impairment. No differences in fluorescence data indicate that T. urticae injury did not impair the function of light harvesting and photoelectron transport. These results showed that T. urticae...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Tetranychus urticae; Insect-plant relationship; Fluorescence; Gas exchange; Photosynthesis.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132009000400005

Gas exchange and leaf specific mass of different foliar cohorts of the wintergreen shrub Aristotelia chilensis (Mol.) stuntz (Eleocarpaceae) fifteen days before the flowering and the fall of the old cohort
Provedor de dados: 52
In the beginning of the spring Aristotelia chilensis sheds the old cohort, forms a new one and flowers. Fifteen days before the flowering and the fall we measured net photosynthesis (A), transpiration (E), water use efficiency (WUE), specific leaf mass (SLM) and area and mass of leaves per branch in old and new cohorts. Under low irradiance the old cohort exhibited higher mean values of A and WUE on area bases (P&lt;0.05). Under high irradiance A and WUE on mass bases were higher in new cohort due to its lower SLM (42.10 gm-2) in relation to old cohort (79.53 gm-2). Because old cohort showed 3.7 times more dry mass per branch it was able to counterbalance its lower performance on mass bases. It was concluded that old cohort was an important source of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aristotelia chilensis; Foliar cohorts; Photosynthesis; Specific leaf mass.
Ano: 2001
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132001000300009

Photosynthetic capacity and water use efficiency in sugarcane genotypes subject to water deficit during early growth phase
Provedor de dados: 52
Autores: Silva,Marcelo de Almeida; Jifon,John Lonfover; Santos,Claudiana Moura dos; Jadoski,Cleber Junior; Silva,Jorge Alberto Gonçalves da.
The objective of this study was to compare the gas exchange, photosynthetic capacity and water potential of sugarcane genotypes cultivated under water deficit conditions imposed during the initial growth phase. Experiments were performed in a greenhouse using two sugarcane genotypes namely: HoCP93-776 (drought susceptible) and TCP02-4587 (drought tolerant). Sixty days after planting, two different water treatments were applied (i.e., with or without water deficit). At 0,30 and 60 days after the treatment, gas exchange variables were evaluated for their relationship with water use, intrinsic instantaneous water use efficiency and instantaneous carboxylation efficiency. The SPAD index, photosynthetic pigments, water potential and relative water content in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Saccharum spp.; Photosynthesis; Stomatal conductance; Chlorophyll; Drought tolerance; Water potential.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132013000500004

Effects of organic fertilizers on the growth and yield of bush bean, winged bean and yard long bean
Provedor de dados: 52
Autores: Islam,Mohammad Aminul; Boyce,Amru Nasrulhaq; Rahman,Md Motior; Azirun,Mohd Sofian; Ashraf,Muhammad Aqeel.
ABSTRACT VC (20%), TC (20%) and N:P:K fertilizer (farmer's practice) were used to determine the growth and yield attributes of bush bean (Phaseolus vulgaris), winged bean (Psophocarpus tetragonolobus) and yard long bean (Vigna unguiculata). Plants grown with VC (20%) produced the highest fresh biomass for bush bean (527.55 g m-2), winged bean (1168.61 g m-2) and yard long bean (409.84 g m-2). In all the tested legumes the highest pod weight, pod number, pod dry weight and pod length were found in the VC (20%) treatment. Photosynthetic rates in the three legumes peaked at pod formation stage in all treatments, with the highest photosynthetic rate observed in winged bean (56.17 µmol m-2s-1) grown with VC (20%). The highest yield for bush bean (2.98 ton...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Vermicompost; Compost; Phaseolus vulgaris; Psophocarpus tetragonolobus and Vigna unguiculata; Photosynthesis; Protein content.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132016000200205

Effects of Allelochemicals from Ficus microcarpaon Chlorella pyrenoidosa
Provedor de dados: 52
Autores: Jiang,Zhongyang; Peiyong,Guo; Chang,Cheinchi; Gao,Lili; Li,Shixiong; Wan,Jinjin.
This study was performed in order to isolate and identify unknown allelochemicals from Ficus microcarpa, and to investigate the inhibitory to bloom-forming of green alga Chlorella pyrenoidosa. Through gradient elution, fraction C2, whose inhibition of alga growth in diverse extracts was the strongest was shown to cause significant reductions of maximum quantum yield, as well as electron transport rates of C. pyrenoidosa. The study data also showed that the increase of fraction C2 concentration decreased the activity of total superoxide dismutase (SOD), but increased the activities of catalase (CAT) and malondialdehyde (MDA) content. These results demonstrate that the active fraction C2 not only induced the photoinhibition or photodamage of PSII reaction...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Allelochemical; Phenols; Photosynthesis; Ficus microcarpa; Chlorella pyrenoidosa.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132014000400595

Intensity of bitterness of processed yerba mate leaves originated in two contrasted light environments
Provedor de dados: 52
Autores: Rakocevic,Miroslava; Medrado,Moacir José Sales; Lucambio,Fernando; Valduga,Alice Teresa.
The bitterness intensity of beverage prepared from the leaves produced on the males and females of yerba mate (Ilex paraguariensis), grown in the forest understory and monoculture, was evaluated. The leaves were grouped by their position (in the crown and on the branch tips) and by the leaf age. The leaf gas exchange, leaf temperature and photosynthetic photon flux density were observed. Inter and intra-specific competition for light and self-shading showed the same effect on yerba mate beverage taste. All the shading types resulted in bitterer taste of the processed yerba mate leaves compared to the leaves originated under the direct sun exposure. The leaves from the plants grown in the monoculture showed less bitterness than those grown in the forest...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Leaf age; Photosynthesis; Shade; Stomatal conductance; Temperature; Transpiration.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132008000300018

Physiological aspects of sun and shade leaves of Lithraea molleoides (Vell.) Engl. (Anacardiaceae)
Provedor de dados: 52
Autores: Dias,Jaqueline; Pimenta,José Antonio; Medri,Moacyr Eurípedes; Boeger,Maria Regina Torres; Freitas,Claudinei Toledo de.
The aim of this work was to compare the physiological parameters of sun and shade leaves of a specimen of L. molleoides. The higher-positional leaves, classified as sun leaves, presented similar photosynthetic rate, lower chlorophyill contents (a, b and total), same a chlorophyll /b chlrorophyll rate, lower transpiratory rate, same stomatal conductance and intercellular concentration of CO2 as the lower-positional leaves, classified as shade leaves. Nutrient concentration, except for Ca and Mg, was the same for both sun and shade leaves.The physiological parameter responses indicated that although receiving lower light intensity, the shade leaves had the same capacity to grow and develop as the sun leaves.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Sun leaves; Shade leaves; Light intensity; Chlorophyll; Lithraea molleoides.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132007000100011

Growth and photosynthetic capacity in two woody species of cerrado vegetation under different radiation availability
Provedor de dados: 52
Autores: Ronquim,Carlos Cesar; Prado,Carlos Henrique B. de A.; Paula,Nádia Figueiredo de.
Seedlings of two woody species of cerrado vegetation, Copaifera langsdorffii and Eriotheca gracilipes, were studied under three different radiation availability (100, 80 and 30% transmittance). Full solar radiation brought about more biomass, higher total leaf area, higher maximal photosynthesis per crown on area or on mass bases and higher photosynthetic capacity on area bases. Only the photosynthetic capacity values on leaf mass bases were higher in both species under low radiation availability (80 and 30% transmittance). The differences of accumulated biomass appeared more clearly after 4 months of sowing but the root/shoot dry biomass ratio and height were maintained constant for both species independently of the available radiation. Cultivated under...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Biomass allocation; Cerrado; Copaifera langsdorffii; Eriotheca gracilipes; Growth in shade; Photosynthesis.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132003000200016

Effects of light on the growth and photosynthesis of Egeria najas planchon
Provedor de dados: 52
Autores: Tavechio,Washington Luiz Gomes; Thomaz,Sidinei Magela.
Photosynthesis and growth of Egeria najas (Hydrocharitaceae) from a subtropical reservoir (Itaipu Reservoir, Brazil-Paraguay) were measured in response to low light intensities (0-124 µM m-2 s-1 PAR) in the laboratory. Photosynthesis approached saturation in the range of light intensities used and light compensation point was reached at ca. 6-22 µM m-2 s-1 PAR, indicating that this species had a low light requirement for growth. Light stimulated shoot and root relative growth rates (RGR) but it was not related to ratios between root:shoot RGR. Laboratory observations indicated that (i) both shoot and root growth were simultaneously stimulated by light and (ii) the low light requirements of E. najas may explain its incidence in the Itaipu Reservoir, where...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Egeria najas; Photosynthesis; Growth; Light compensation point; Rooted macrophytes.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132003000200011

Morphological and physiological responses of Cedrela Fissilis Vellozo (Meliaceae) seedlings to light
Provedor de dados: 52
Autores: Santos,Débora Leonardo dos; Rakocevic,Miroslava; Takaki,Massanori; Ribaski,Jorge.
Seeds of Cedrela fissilis Vellozo were planted and maintained under two distinct conditions: at east border of a forest with red: far-red ratio of 1.15 and under canopy with photosynthetic photon flux density of 0.22-7% of full sun radiation and red: far-red ratio of 0.21-0.36. Seedling growth (height and stem diameter) was faster under sun, the development of roots more continuous and the number of leaves almost twice of that of shade plants. The leaf area was 10 times greater in sun plants with 15-25 leaflets per leaf while under shade only 5 to 10 leaflets were found per leaf. In shade plants, a higher proportion of dry mass was found in aerial parts. Leaves of sun plants had the capacity of gas exchange to respond to high light radiation, but leaves...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Seedling morphogenesis; Shade.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132006000100020

Research on Phosphorus Removal in Artificial Wetlands by Plants and Their Photosynthesis
Provedor de dados: 52
Autores: Quan,Quan; Shen,Bing; Zhang,Qian; Ashraf,Muhammad Aqeel.
ABSTRACT Urban rainfall runoff pollution has become a major reason for water eutrophication problem in the process of urbanization in China, while phosphorus is a significant restrictive factor that influences primary productivity of freshwater system. It's rather significant to conduct phosphorus control in waste water with engineering measures. This research, based on material balance research of phosphorus in artificial wetlands, HRT (hydraulic retention time) and analysis of wetland plant photosynthesis and removal rate of phosphorus, simulates purification of phosphorus in urban runoff sewage by artificial wetland system. Experiment shows that removal rate of total phosphorus in urban runoff sewage by artificial wetland system reaches 42.23%-60.89%,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Artificial Wetlands; Plants; Photosynthesis; Phosphorus.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132016000200701

Regulation of the expression of NADP-malic enzyme by UV-B, red and far-red light in maize seedlings
Provedor de dados: 56
Autores: Casati,P.; Drincovich,M.F.; Edwards,G.E.; Andreo,C.S.
The induction of nicotinamide adenine dinucleotide phosphate-malic enzyme (NADP-ME) in etiolated maize (Zea mays) seedlings by UV-B and UV-A radiation, and different levels of photosynthetically active radiation (PAR, 400-700 nm) was investigated by measuring changes in activity, protein quantity and RNA levels as a function of intensity and duration of exposure to the different radiations. Under low levels of PAR, exposure to UV-B radiation but not UV-A radiation for 6 to 24 h caused a marked increase in the enzyme levels similar to that observed under high PAR in the absence of UV-B. UV-B treatment of green leaves following a 12-h dark period also caused an increase in NADP-ME expression. Exposure to UV-B radiation for only 5 min resulted in a rapid...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: C4 photosynthesis; NADP-malic enzyme; UV-B radiation; Photosynthesis; Red light; Far-red light.
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999001000002

Physiological response of Cucurbita pepo var. pepo mycorrhized by Sonoran desert native arbuscular fungi to drought and salinity stresses
Provedor de dados: 58
Autores: Harris-Valle,Citlalli; Esqueda,Martín; Gutiérrez,Aldo; Castellanos,Alejandro E.; Gardea,Alfonso A.; Berbara,Ricardo.
ABSTRACT Plants response to symbiosis with arbuscular mycorrhizal fungi (AMF) under water stress is important to agriculture. Under abiotic stress conditions native fungi are more effective than exotics in improving plant growth and water status. Mycorrhization efficiency is related to soil fungi development and energy cost-benefit ratio. In this study, we assessed the effect on growth, water status and energy metabolism of Cucurbita pepo var. pepo when inoculated with native AMF from the Sonoran desert Mexico (mixed isolate and field consortium), and compared with an exotic species from a temperate region, under drought, low and high salinity conditions. Dry weights, leaf water content, water and osmotic potentials, construction costs, photochemistry and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glomus; Pacispora; Water status; Construction cost; Photosynthesis.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822018000100045

Ecophysiology of tea
Provedor de dados: 61
Autores: De Costa,W.A. Janendra M.; Mohotti,A. Janaki; Wijeratne,Madawala A.
Tea [Camellia sinensis (L.) O. Kuntze] is one of the most important beverage crops in the world. The major tea-growing regions of the world are South-East Asia and Eastern Africa where it is grown across a wide range of altitudes up to 2200 m a.s.l.. This paper reviews the key physiological processes responsible for yield determination of tea and discusses how these processes are influenced by genotypic and environmental factors. Yield formation of tea is discussed in terms of assimilate supply through photosynthesis and formation of harvestable sinks (i.e. shoots). The photosynthetic apparatus and partial processes (i.e. light capture, electron transport and carboxylation) of tea show specific adaptations to shade. Consequently, maximum light-saturated...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Climate change; Photoinhibition; Photosynthesis; Shoot growth; Temperature; Vapour pressure deficit; Water potential.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000400005

Gas exchange and yield response to foliar phosphorus application in Phaseolus vulgaris L. under drought
Provedor de dados: 61
Autores: Santos,Mauro Guida dos; Ribeiro,Rafael Vasconcelos; Oliveira,Ricardo Ferraz de; Pimentel,Carlos.
This study was conducted to evaluate the effect of foliar Pi application on gas exchange and yield of bean genotypes submitted to a mild water deficit at the pre-flowering stage. In the first experiment, when extra Pi (10 g.L-1) was sprayed on leaves during water stress or during recovery, there was no effect on gas exchange or yield in the A320, Carioca and Ouro Negro genotypes. However, net CO2 assimilation (A) of A320 and Ouro Negro was less affected, but not significantly, than Carioca at the end of the stress, when Pi was supplied five days before water deficit. In the second experiment, two different doses of Pi (10 and 20 g.Pi L-1) were sprayed five days before water deficit on the Carioca genotype. During the last three days of the mild water...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Common bean; Inorganic phosphorus; Photosynthesis; Water deficit.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202004000300007

Leaf and fruiting phenology and gas exchange of Mangabeira in response to irrigation
Provedor de dados: 61
Autores: Lobo,Francisco de A.; Campelo Junior,José H.; Rodríguez-Ortíz,Carmen E.; Lucena,Isabela C. de; Vourlitis,George L.
The mangabeira (Hancornia speciosa Gómez) is a native species of Brazil occurring in the savanna (Cerrado) and Atlantic Coastal forests. It is a promising species for large-scale horticulture due to the high-protein properties of its fruits, but extensive cultivation has not yet been accomplished. Research is still needed to determine cultivation techniques that will optimize productivity. As irrigation is considered to be the most important agronomic technique to enhance productivity, the goal of this investigation was to evaluate the effects of irrigation on leaf gas exchange (net photosynthesis rate and transpiration rate) and foliar and fruiting phenology. Our results suggest that irrigation acts by increasing the growth and fruit production of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Hancornia speciosa; Neotropical savanna; Photosynthesis; Specific leaf area.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202008000100001

Impacts of drought and temperature stress on coffee physiology and production: a review
Provedor de dados: 61
Autores: DaMatta,Fábio M.; Ramalho,José D. Cochicho.
Overall, drought and unfavourable temperatures are the major climatic limitations for coffee production. These limitations are expected to become increasingly important in several coffee growing regions due to the recognized changes in global climate, and also because coffee cultivation has spread towards marginal lands, where water shortage and unfavourable temperatures constitute major constraints to coffee yield. In this review, we examine the impacts of such limitations on the physiology, and consequently on the production of mainly Coffea arabica and C. canephora, which account for about 99 % of the world coffee bean production. The first section deals with climatic factors and the coffee plant’s requirements. The importance of controlling oxidative...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Coffea; Chilling; Frost; Heat; Photosynthesis; Water deficit; Water use; Yield.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000100006

Morpho-physiological responses of cowpea leaves to salt stress
Provedor de dados: 61
Autores: Lacerda,Claudivan F.; Assis Júnior,José O.; Lemos Filho,Luiz C. A.; Oliveira,Teógenes S. de; Guimarães,Francisco V.A.; Gomes-Filho,Enéas; Prisco,José T.; Bezerra,Marlos A.
The effect of salt stress of known intensity and duration on morpho-physiological changes in leaves of different ages from cowpea [Vigna unguiculata (L.) Walp.] plants was studied, aiming for a better understanding of the acclimation process of the whole-plant. Seeds were sown in vermiculite and seedlings were transferred to plastic trays containing aerated nutrient solution, and kept in a greenhouse. When the first trifoliate leaf emerged the seedlings were transplanted into 3 L plastic pots containing aerated nutrient solution. Salt additions started 5 d later, and the salt-treated plants received 25 mmol L-1 per day until reaching a final concentration of 75 mmol L-1. During the experimental period primary leaves and the 1st, 2nd, and 3rd trifoliate...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ion concentration; Photosynthate partitioning; Photosynthesis; Salinity; Stress acclimation.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000400003

Effects of n-propyl gallate on photosynthesis and physiological parameters in Dunaliella salina are affected by stressful conditions
Provedor de dados: 61
Autores: Einali,Alireza; Shariati,Mansour.
We studied the effects of n-propyl gallate, which is a plastid terminal oxidase inhibitor involved in chlororespiration, on photosynthesis and physiological parameters in Dunaliella salina grown under different salinities and under low or high irradiance using chlorophyll a fluorescence transient measurements and pigment analysis. The inhibitor up to 1 mM had an additive significant effect on the photosynthetic efficiency in the cell suspensions grown under low salinity and irradiance. However, in the presence of high n-propyl gallate concentration (4 mM), there was a negative effect on all physiological aspects. In contrast, this high concentration of the inhibitor could enhance efficiency of electron transport and growth parameters under high irradiance....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chlorophyll fluorescence; Dunaliella salina; Light intensity; Photosynthesis; Salt stress.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202012000300006

Effects of flooding and shading on growth and gas exchange of Vochysia divergens Pohl (Vochysiaceae) of invasive species in the Brazilian Pantanal
Provedor de dados: 61
Autores: Dalmolin,Ândrea Carla; Dalmagro,Higo José; Lobo,Francisco de Almeida; Antunes Junior,Mario Zortéa; Ortíz,Carmen Eugenia Rogríguez; Vourlitis,George Louis.
Vochysia divergens Pohl (commonly known as cambara) is a pioneer tree species that is native to the Amazon Basin but has been invading the seasonally flooded wetlands of the Brazilian Pantanal, forming monospecific communities. The physiological aspects associated with cambara invasion, including the effects of flooding and shading on growth and leaf gas exchange, are unknown but may shed light on why cambara is able to invade this novel habitat so rapidly. Thus, we conducted a manipulative experiment to quantify the effects of shading and flooding on the growth, gas exchange and leaf nutrient content of V. divergens saplings. Based on previous research we hypothesized that (1) experimental flooding would have no effect on the growth and gas exchange of V....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cambara; Physiological stress; Photosynthesis; Plant ecophysiology; Stomatal conductance; Tropical wetlands.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202012000200001

Study of the effect of Aliette on the activity of spinach (Spinacea oleracea L.) chloroplasts
Provedor de dados: 61
Autores: Almeida,Pedro; Coutinho,João P.; Rocha,João; Gomes-Laranjo,José.
Intensification of production in modern agriculture is frequently obtained thanks to the increase of pesticide applications and chemical fertilizers. However, the use of these products sometimes causes a reduction of crop productivity. We aimed to evaluate the impact of the fungicide Aliette on in vitro activity of chloroplasts of spinach (Spinacea oleracea L.). Transmembrane potential formation, PSII oxygen evolution and PSII photochemistry were analyzed. Our results showed that the recommended concentration (2.5 g L-1) of Aliette did not impair the photosynthetic apparatus. However, at higher concentrations (&gt; 7.5 g L-1), reductions in thylakoid membrane potential and oxygen evolution were recorded, but with no evidence of photoinhibition.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bioenergetics; Ecotoxicology; Pesticides; Photosynthesis; Xenobiotics.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000100009

Effect of cobalt on growth, pigments and the photosynthetic electron transport in Monoraphidium minutum and Nitzchia perminuta
Provedor de dados: 61
Autores: El-Sheekh,M.M.; El-Naggar,A.H.; Osman,M.E.H.; El-Mazaly,E.
The unicellular green alga Monoraphidium minutum and the diatom Nitzschia perminuta were cultured under different concentrations of Co2+. Growth and pigment content were slightly increased at low concentrations and inhibited by high Co2+ concentrations. The results concerning the effect of different concentrations of Co2+ on photosynthetic O2 evolution showed a reduction in the amount of O2 evolved by each alga in response to increasing Co2+ concentrations. However, an increase in O2 evolution for both M. minutum and N. perminuta was observed at relatively low Co2+ concentrations. Photosynthetic electron transport in M. minutum was more sensitive to Co2+ toxicity than in N. perminuta. On the other hand, the effect of the heavy metal on respiration showed...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cobalt; Diatoms; Green algae; Pigments; Photosynthesis.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202003000300005

The complexity-stability hypothesis in plant gas exchange under water deficit
Provedor de dados: 61
Autores: Souza,Gustavo M.; Pincus,Steven M; Monteiro,José Alberto F.
We hypothesized that more complex, i.e. irregular, temporal dynamics and a more interconnected overall network supports greater stability to gas exchange parameters (herein, CO2 net assimilation and transpiration) in plants under water deficit. To test this hypothesis two genotypes of Phaseolus vulgaris were subjected to a period of absence of irrigation, and subsequent rewatering to achieve recovery. Gas exchanges parameters were measured each 10 s during 6 h to obtain time series to evaluate complexity by Approximate Entropy (ApEn) calculations, and network connectance in each water regime. Notably, the Jalo Precoce genotype showed significantly more stability than the Guarumbé genotype under system perturbation, coincident with greater irregularity in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Approximate Entropy; Complexity; Network connectance; Plant stress theory; Photosynthesis; Temporal dynamics; Water deficit.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202005000400004

Partitioning of nitrate reductase activity in Coffea arabica L. and its relation to carbon assimilation under different irradiance regimes
Provedor de dados: 61
Autores: Carelli,Maria Luiza C.; Fahl,Joel I.
The distribution of in vivo nitrate reductase (EC 1.6.6.1) activity (NRA) between leaves and roots was studied in young coffee plants (Coffea arabica L.) grown in pots with watered sand in a glasshouse and irrigated with nutrient solution. The influence of irradiance regimes on the partitioning of NRA, and its relation with CO2 assimilation, was also evaluated in plants grown under approximately 20, 50 and 100% of full sunlight. Time-course of nitrate accumulation in nitrogen-starved plants showed a similar pattern in leaves and roots after supplying 15 mmol L-1 nitrate, indicating efficient ability of the roots to export nitrate to the shoot. At the same time, NRA was rapidly induced in both tissues. In shoots, NRA partitioning was synchronized among the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Coffee; Growth; Leaf/root ratio; Nitrate assimilation; Photosynthesis; Shading.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000300006

Seasonal leaf gas exchange and water potential in a woody cerrado species community
Provedor de dados: 61
Autores: Prado,Carlos Henrique Britto de Assis; Wenhui,Zhang; Cardoza Rojas,Manuel Humberto; Souza,Gustavo Maia.
Predawn leaf water potential (psipd) and morning values of leaf gas exchange, as net photosynthesis (A), stomatal conductance (gs), transpiration (E), and morning leaf water potential (psimn) were determined seasonally in 22 woody cerrado species growing under natural conditions. Despite the lower mean values of psipd in the dry season (-0.35 ± 0.23 MPa) compared to the wet season (-0.08 ± 0.03 MPa), the lowest psipd in the dry season (-0.90 ± 0.00 MPa) still showed a good nocturnal leaf water status recovery for all species studied through out the year. Mean gs values dropped 78 % in the dry season, when the vapor pressure of the air was 80% greater than in the wet season. This reduction in gs led to an average reduction of 33% in both A and E, enabling...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cerrado; Deciduousness; Network connectance; Stomatal conductance; Photosynthesis.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202004000100002

Leaf heliotropism in Styrax camporum Pohl from the Brazilian cerrado: distinct gas exchange and leaf structure, but similar leaf temperature and water relations
Provedor de dados: 61
Autores: Habermann,Gustavo; Machado,Silvia R.; Guimarães,Vandeir F.; Rodrigues,João D.
Styrax camporum is a common shrub species from the cerrado regions of São Paulo State, Brazil. Although its leaves do not have a morphologically delimited pulvinus, the apical leaves are oriented parallel to the sun (paraheliotropic leaves), most notably around noon. Horizontal leaves at the base of shoots are oriented perpendicular to the sun's rays (diaheliotropic leaves). The ecophysiological significance of this is not fully understood. We investigated how paraheliotropism influences daily CO2 assimilation (A) and other gas exchange rates, water relations, leaf temperature (Tl), and how these relate to leaf structure as assessed by anatomical leaf descriptions. Paraheliotropic leaves had greater A and stomatal conductance (g s), which led to greater...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Brazilian savanna; Ecophysiology; Gas exchange; Leaf movements; Leaf temperature; Photosynthesis; Styracaceae.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202008000100008

Carbon isotope composition and leaf anatomy as a tool to characterize the photosynthetic mechanism of Artemisia annua L.
Provedor de dados: 61
Autores: Marchese,José Abramo; Broetto,Fernando; Ming,Lin Chau; Ducatti,Carlos; Rodella,Roberto Antonio; Ventrella,Marília Contin; Gomes,Greice Daiane Rodrigues; Franceschi,Lúcia de.
Leaves of Artemisia annua L. are a plentiful source of artemisinin, a drug with proven effectiveness against malaria. The aim of this study was to classify the photosynthetic mechanism of A. annua through studies of the carbon isotope composition (delta 13C) and the leaf anatomy. A. annua presented a delta 13C value of - 31.76 ± 0.07, which characterizes the plants as a typical species of the C3 photosynthethic mechanism, considering that the average delta 13C values for C3 and C4 species are -28 and -14, respectively. The leaf anatomy studies were consistent with the delta 13C results, where, in spite of the existence of parenchymatic cells forming a sheath surrounding the vascular tissue, the cells do not contain chloroplasts or starch. This...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: C3 and C4 plants; Isotope discrimination; Kranz anatomy; Photosynthesis.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202005000100016

Physiological disturbances promoted by ozone in five cultivars of Phaseolus vulgaris L.
Provedor de dados: 61
Autores: Clebsch,Cláudia C.; Divan Junior,Armando M.; Oliveira,Paulo L.; Nicolau,Márcio.
Bean seedlings of Fepagro 26, Guapo Brilhante, Iraí, Macotaço and US Pinto 111 cultivars were submitted to treatments with or without addition of ozone to the ambient air, in order to evaluate the effects of exposure on photosynthesis, relative electrolyte leakage, foliar abscission and biomass of the seedlings. Exposure to ozone caused significant decreases in the net assimilation of all cultivars except Iraí. It also caused a significant increase in electrolyte leakage from the Pinto cultivar, but only when AOT40 was the highest. It also produced significant anticipation in the time of foliar abscission in the Pinto, Fepagro and Guapo cultivars. The variability observed in the biomass measurements reflected the limitations to perform long-term...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Relative electrolyte leakage; Foliar abscission; Biomass.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202009000400008

Ecophysiology of papaya: a review
Provedor de dados: 61
Autores: Campostrini,Eliemar; Glenn,David M.
Papaya (Carica papaya L.) is a principal horticultural crop of tropical and subtropical regions. Knowledge of how papaya responds to environmental factors provides a scientific basis for the development of management strategies to optimize fruit yield and quality. A better understanding of genotypic responses to specific environmental factors will contribute to efficient agricultural zoning and papaya breeding programs. The objective of this review is to present current research knowledge related to the effect of environmental factors and their interaction with the photosynthetic process and whole-plant physiology. This review demonstrates that environmental factors such as light, wind, soil chemical and physical characteristics, temperature, soil water,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Carica papaya; Environmental factors; Photosynthesis; Water relations; Water-use efficiency.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000400010

Aspects of nitrogen metabolism in coffee plants
Provedor de dados: 61
Autores: Carelli,Maria Luiza Carvalho; Fahl,Joel Irineu; Ramalho,José D. Cochicho.
Coffee plants are highly N-demanding plants. Despite the importance of N nutrition for the development, acclimation and yield of coffee plants, there are few reports concerning N metabolism in this species. In this review, our intention is to summarize the information available in the literature and to point out the influence of environmental conditions on N assimilation, as well as comment and discuss some apparently contradictory results and raise and enlighten queries about N assimilation in coffee plants.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Coffea; Irradiance level; Nitrate reductase; Nitrogen fertilization; Oxidative stress; Photoinhbition; Photoprotection; Photosynthesis.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000100002

Differential responses of ribulose-1,5-bisphosphate carboxylase/oxygenase activities of two Vigna unguiculata cultivars to salt stress
Provedor de dados: 61
Autores: Aragão,Maria Erivalda Farias de; Guedes,Marjorie Moreira; Otoch,Maria de Lourdes Oliveira; Guedes,Maria Izabel Florindo; Melo,Dirce Fernandes de; Lima,Maria da Guia Silva.
Vita 3 and Vita 5 are two Vigna unguiculata cultivars that differ in their capacities for survival in saline environments; Vita 3 is more tolerant and Vita 5 more sensitive. Both cultivars were submitted to salt stress with 0.1 M NaCl. After 8 days, root and shoot growth from both cultivars was reduced but reduction was more pronounced in Vita 5. Furthermore, leaf area was also reduced in this cultivar. Chlorophyll content and chlorophyll fluorescence parameters were not affected by salt stress, but the specific activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) decreased in Vita 3 and increased in Vita 5. The use of immunological techniques also revealed that the Rubisco content from Vita 3 decreased while that of Vita 5 increased....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Rubisco; Photosynthesis; Salt stress; Vigna unguiculata.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202005000200003

Growth and photosynthetic responses of Picea asperata seedlings to enhanced ultraviolet-B and to nitrogen supply
Provedor de dados: 61
Autores: Yao,Xiaoqin; Liu,Qing; Han,Chao.
Ultraviolet-B (UV-B) radiation and nitrogen are expected to increase simultaneously with future changes in global climate. In this study, growth and photosynthetic responses of Picea asperata seedlings to enhanced UV-B and to nitrogen supply were studied. The experimental design included two levels of UV-B treatments (ambient UV-B, 11.02 kJ m-2 d-1; enhanced UV-B, 14.33 kJ m-2 d-1) and two nitrogen levels (0; 20 g N m-2) to determine whether nitrogen can alleviate the negative impacts of enhanced UV-B on seedling growth and photosynthesis. Enhanced UV-B significantly inhibited plant growth and impaired net photosynthetic rate, stomatal conductance, transpiration rate, the light-saturated assimilation rate, assimilation capacity, light compensation point,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Growth; Gas exchange; Nitrogen; Picea asperata; Photosynthesis; UV-B.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202008000100002

The chlorophyll a fluorescence as an indicator of the temperature stress in the leaves of Prunus persica
Provedor de dados: 61
Autores: Martinazzo,Emanuela Garbin; Ramm,Aline; Bacarin,Marcos Antonio.
Plants growing in temperate regions are often exposed to stress conditions caused by high temperatures. Photosynthesis is one of the metabolic processes most sensitive to high temperature stress, and it is often inhibited before other cellular functions. Using peach leaf disks, we studied the transient chlorophyll a fluorescence along with the gas exchanges at temperatures of 25 (control) 30, 35, 40 and 45°C in the dark for a period of 30 minutes. Temperatures above 35°C caused significant changes in the transient fluorescence of chlorophyll a, including an increase in the initial fluorescence (F0), a decrease in maximum fluorescence values (F M) and the appearance of K and L bands. The values of the net assimilation rate decreased as the temperature...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: High temperature; Photosynthesis; Prunus persica.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202012000400002

Photoacclimation in three species of freshwater red algae
Provedor de dados: 61
Autores: Bautista,Anna I.N.; Necchi Jr.,Orlando.
Three freshwater Rhodophyta species (Audouinella eugenea, A. hermannii and Compsopogon coeruleus) were tested as to their responses (photosynthesis, growth and pigment concentration) to two irradiances (low light, LL, 65 µmol m-2 s-1 and high light, HL, 300 µmol m-2 s-1) and two periods (short time, ST, 4 d, and long time, LT, 28 d). Higher growth rates were consistently observed at LL but significant differences were observed only for A. hermannii. Higher values of photoinhibition at LL were found for the three species, which is consistent with the dynamic photoinhibition as a reversible photoprotective mechanism against high irradiance. Light-induced decreases of effective quantum yield (EQY) were observed in the three species consisting of pronounced...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chlorophyll fluorescence; Growth; Irradiance; Photosynthesis; Pigment; Red algae.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000100003

Ecophysiology of tropical tree crops: an introduction
Provedor de dados: 61
Autores: DaMatta,Fábio M.
In this special issue, ecophysiology of major tropical tree crops, considered here on a broader sense and including species such as banana, cashew, cassava, citrus, cocoa, coconut, coffee, mango, papaya, rubber, and tea, are examined. For most of these crops, photosynthesis is treated as a central process affecting growth and crop performance. The crop physiological responses to environmental factors such as water availability and temperature are highlighted. Several gaps in our database concerning ecophysiology of tropical tree crops are indicated, major advances are examined, and needs of further researches are delineated.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Crop growth and production; Environmental stresses and physiology; Photosynthesis; Gas exchange; Tropical tree crops.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000400001

Gas exchanges and carbohydrate metabolism in orangetrees with citrus variegated chlorosis
Provedor de dados: 61
Autores: Gomes,Mara de Menezes de Assis; Lagôa,Ana Maria Magalhães Andrade; Machado,Eduardo Caruso; Medina,Camilo Lázaro; Machado,Marcos Antônio.
Gas exchanges, sucrose, starch and reducing sugar contents were analyzed in leaves of orange trees with and without Citrus Variegated Chlorosis (CVC), a disease caused by the bacteria Xylella fastidiosa. Healthy plants (HP) and diseased plants (DP) were evaluated 20 and 26 months after bacterial inoculation, in October 1998 and April 1999, respectively. On the first evaluation date, CO2 assimilation rates for HP were greater than DP in the early morning and midday, but on the second date they were greater in HP all along the day. On the first date, there was an increase in the sucrose content of DP at 15:00 h and 17:00 h in relation to HP. On the second evaluation date, DP presented greater reducing sugar content only in the early morning while sucrose...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Citrus sinensis L.; Photosynthesis; Reducing sugars; Starch; Sucrose; Xylella fastidiosa.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202003000100004

Photosynthetic characteristics of a tropical population of Nitella cernua (Characeae, Chlorophyta)
Provedor de dados: 61
Autores: Vieira Jr.,Jair; Necchi Jr.,Orlando.
Photosynthetic characteristics (assessed by chlorophyll fluorescence and O2 evolution) were analysed monthly during one year in a tropical population of Nitella cernua from southeastern Brazil (20º50'32" S, 49º26'15" W). Parameters derived from photosynthesis-irradiance (PI) curves by fluorescence (high values of the photosynthetic parameter, Ik, and lack or low values of photoinhibition, beta) suggested adaptation to high irradiance, whereas those by O2 evolution showed a different pattern (low values of Ik and compensation irradiance, Ic, high values of photosynthetic efficiency, alpha, and photoinhibition). Parameters from PI curves by O2 evolution suggested light acclimation: Ik and maximum photosynthetic rate, Pmax (as rETR, relative electron transfer...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Charophytes; Irradiance; Nitella; PH; Photosynthesis; Seasonal dynamics; Temperature.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000300004

High temperature effects on the response of photosynthesis to light in sweet orange plants infected with Xylella fastidiosa
Provedor de dados: 61
Autores: Ribeiro,Rafael Vasconcelos; Machado,Eduardo Caruso; Oliveira,Ricardo Ferraz de; Pimentel,Carlos.
The objective of this study was to evaluate the high temperature effects on the response of photosynthesis to light in sweet orange plants infected with Xylella fastidiosa. This vascular bacterium is the causal agent of the citrus variegated chlorosis that causes severe economical losses to the Brazilian citrus industry. The responses of the photosynthetic oxygen evolution and the parameters related to chlorophyll a fluorescence to the increase in light intensity were evaluated at 35ºC and 45ºC in both healthy and infected leaf discs. The increase in temperature affected the photosynthetic apparatus of both healthy and infected plants, although infected plants showed higher photochemical sensitivity at the higher temperature (e.g. in the potential quantum...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chlorophyll fluorescence; Citrus sinensis; Light response curve; Photosynthesis; Temperature; Xylella fastidiosa.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202003000200004

Glomus intraradices improved salt tolerance in Prosopis alba seedlings by improving water use efficiency and shoot water content
Provedor de dados: 61
Autores: Scambato,Agustina A.; Echeverria,Mariela; Sansberro,Pedro; Ruiz,Oscar A.; Menéndez,Ana Bernardina.
The present work was aimed at testing the hypothesis that mycorrhizal Prosopis alba, an economically important tree species worldwide, presents increased salt-tolerance compared with non-mycorrhizal ones and at gaining insight into the possible mechanisms underlying that improvement. For this purpose, a randomized complete block experiment with two factors: mycorrhizal treatments with or without the arbuscular fungus Glomus intraradices and two salinity levels, 0 and 200 mM NaCl was performed. Plant growth in P. alba plants colonized by G. intraradices was less affected by salinity than that in non-arbuscular mycorrhizal (AM) plants, indicating that mycorrhizal colonization turned P. alba more tolerant to salinity. Photosynthesis was reduced by salinity in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Salinity; Stomatal conductance; Transpiration ratio; Proline.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202010000400008

Effects of hydric deficiency on gas exchange parameters and metabolism of Eucalyptus grandis clones
Provedor de dados: 61
Autores: Coscolin,Renata B. S.; Broetto,Fernando; Marchese,José A.; Campohermoso,Marco C.; Paladini,Marcos V.
The metabolic effects caused by hydric deficiency (HD) on Eucalyptus grandis clones were assessed by an experiment where plants were cultivated in four blocks. The first was the control block, normally irrigated, whereas the other three blocks were submitted to cycles of hydric deficiency. Analysis of photosynthetic efficiency, enzymatic activity of antioxidant response system, level of pigments and L-proline concentration were performed to evaluate the HD effects. Results showed that HD altered some parameters related to photosynthetic activity, pigments accumulation, proline and enzymatic activity. Clone 433 of E. grandis presented higher response ability to HD.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Enzymes; Eucalypt; Hydric deficiency; Photosynthesis.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202011000400002

Environmental physiology of the bananas (Musa spp.)
Provedor de dados: 61
Autores: Turner,David W.; Fortescue,Jeanie A.; Thomas,Dane S.
The bananas are thought to be particularly sensitive to changes in the environment. This review considers some historical and recent investigations into the response of the leaf, root and reproductive system to the environment. Monteith's analysis of the response of plants to intercepted radiation is appropriate for analyzing the productivity of bananas and plantains. The banana is sensitive to soil water deficits, and expanding tissues such as emerging leaves and growing fruit are among the first to be affected. As soil begins to dry, stomata close and leaves remain highly hydrated, probably through root pressure. Productivity is affected because of the early closure of stomata. We find the common belief that bananas use large amounts of water does not...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Crop yield; Leaf system; Light; Photoperiod; Photosynthesis; Reproductive system; Root system; Temperature; Water supply.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000400013

Establishment of sensitive and resistant variety of tomato on the basis of photosynthesis and antioxidative enzymes in the presence of cobalt applied as shotgun approach
Provedor de dados: 61
Autores: Hasan,Syed Aiman; Hayat,Shamsul; Wani,Arif Shafi; Ahmad,Aqil.
Cobalt (Co) affords both beneficial as well as toxic effects to plants. The present study was performed with an aim to find out the varietal differences among five tomato cultivars against the Co induced changes in growth, photosynthesis, nitrate reductase (E.C.1.6.6.1), carbonic anhydrase (E.C.4.2.1.1), antioxidative enzymes i.e. peroxidase (E.C.1.11.1.7), catalase (E.C.1.11.1.6), superoxide dismutase (E.C.1.15.1.1) and that of proline content. Seeds of tomato (varieties, K-25, NTS-9, NBR-Uday, Sarvodya, and Malti) were soaked in 0, 100, 200 or 300 µM CoCl2 for 0, 4, 8, 12 h (shotgun approach) and sampled at 30 days after sowing. All the varieties showed significantly different response to different treatment combinations. Despite substantial varietal...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antioxidative enzyme; Carbonic anhydrase; Cobalt; Nitrate reductase; Photosynthesis; Tomato.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202011000300001

Foliar phosphorus supply and CO2 assimilation in common bean (Phaseolus vulgaris L.) under water deficit
Provedor de dados: 61
Autores: Santos,Mauro G. dos; Ribeiro,Rafael V.; Teixeira,Marcelo G.; Oliveira,Ricardo F. de; Pimentel,Carlos.
Two common bean cultivars were grown in pots under greenhouse conditions. Plants were submitted to a foliar Pi spray two days before suspending irrigation, what enhanced net CO2 assimilation rate of Ouro Negro cultivar but did not change significantly the photosynthesis of Carioca cultivar under both water deficit and rehydration periods. The results revealed that a foliar Pi spray induced an up-regulation of photosynthesis in common bean under mild water deficit, with this effect being genotype-dependent.
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Drought stress; Ortophosphate; Photosynthesis; Water deficit.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000300007

Use of the QTL approach to the study of soybean trait relationships in two populations of recombinant inbred lines at the F7 and F8 generations
Provedor de dados: 61
Autores: Vieira,Antonio José Dias; Oliveira,Dario Alves de; Soares,Taís Cristina Bastos; Schuster,Ivan; Piovesan,Newton Deniz; Martínez,Carlos Alberto; Barros,Everaldo Gonçalves de; Moreira,Maurílio Alves.
This work aimed to identify the quantitative trait loci (QTL) associated with photosynthesis and growth and productivity traits of soybean and to study possible associations between these traits by the analysis of coincidence of QTL in linkage groups (LGs). Thus, populations of recombinant inbred lines (RILs) of the F7 and F8 generations derived from the cross between the varieties BARC-8 and Garimpo were used. The traits evaluated were net assimilation rate of CO2 under saturating light (Asat), potential photosynthesis rate (Pmax), leaf area (A), specific leaf area (SLA), specific leaf nitrogen (N); root (W R), nodule (W N), stem (W ST), leaf (W L), pod (W P) and plant dry mass (W T); nodule (nN), seed (n s), and pod number (nP); seed fresh mass per plant...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glycine max; Correlation; Genes; Photosynthesis; Quantitative trait loci.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000200004

Photosynthetic performance in jack bean [Canavalia ensiformis (L.) D.C.] under drought and after rehydration
Provedor de dados: 61
Autores: Zanella,Fábio; Watanabe,Tania Misae; Lima,Ana Lúcia da Silva; Schiavinato,Marlene Aparecida.
The effects of drought and rehydration on Canavalia ensiformis (L.) D.C. (jack bean) plants were evaluated using the following gas exchange parameters: net carbon assimilation rate (A), stomatal conductance (g s), Ci/Ca ratio and transpiration rate (E); chlorophyll a fluorescence: Fv/Fm and Fv/F0 ratio. The plants were cultivated under greenhouse conditions and after 30 days from the emergence, irrigation was suspended in the plants submitted to drought, to obtain the following predawn leaf water potential (psipd): -0.40 MPa (control), -1.00 MPa (moderate drought) and -2.30 Mpa (severe drought). Afterwards, the gas exchange and fluorescence analysis were initiated , and 24 h after rehydration the same analyses were repeated. The A, E, g s and Ci/Ca values...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Fluorescence; Moderate drought; Photosynthesis; Severe drought; Stomatal conductance.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202004000300008

Photo-oxidative stress in coconut seedlings: early events to leaf scorching and seedling death
Provedor de dados: 61
Autores: Naresh,Kumar S.; Kasturi Bai,K.V.
Experiments were conducted on coconut seedlings to delineate events of photo-oxidative stress damage. Studies on chlorophyll fluorescence indicated a clear case of excess light energy under high light conditions causing stress to coconut seedlings raised under coconut palms. Quantum yield of photo-chemistry of leaflets exposed to high light was significantly less than those under shade. Seedlings exposed to high light and then shifted to shade have shown significant improvement in quantum yield. Excess light energy harvested by chlorophyll antenna caused high non-photochemical quenching resulting in production of biologically toxic super oxide, hydrogen peroxide and hydroxyl radicals. It is apparent that photoinhibition of photosynthesis takes place due to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cocos nucifera; Chlorophyll fluorescence; Oxidative stress; Photosynthesis; Lipid peroxidation; Gas exchange; Proteins.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202009000300006

Photochemical efficiency in bean plants (Phaseolus vulgaris L. and Vigna unguiculata L. Walp) during recovery from high temperature stress
Provedor de dados: 61
Autores: Costa,Ernany Santos; Bressan-Smith,Ricardo; Oliveira,Jurandi Gonçalves de; Campostrini,Eliemar; Pimentel,Carlos.
Bean (Phaseolus vulgaris L., cv. Carioca and cv. Negro Huasteco) and cowpea plants (Vigna unguiculata L. Walp cv. Epace 10) were grown in a growth chamber with PPF at leaf level of 200 mumol.m-2.s-1 and air temperature 25 + 1 ºC. The first fully expanded pair of leaves of 12-day-old plants was submitted to high temperature stress (25, 30, 35, 40, 45 and 48 ºC) for 1.5 h. The photochemical efficiency of PSII during recovery was monitored by means of chlorophyll a fluorescence at six different times (0.5, 1, 2, 4, 24, and 48 h) after stress, at 25 ºC, using a modulated fluorimeter. Increasing temperature promoted an increase in Fphi at 45 ºC, possibly associated with dissociation of the light harvesting complex from the reaction centre of PSII, but a...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chlorophyll a fluorescence; Heat stress; Photosynthesis.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000200004

Model Validation for Estimating the Leaf Stomatal Conductance in cv. Cabernet Sauvignon Grapevines
Provedor de dados: 117
Autores: Jara-Rojas,Francisco; Ortega-Farías,Samuel; Valdés-Gómez,Héctor; Poblete,Carlos; del Pozo,Alejandro.
The coupled model of assimilation and stomatal conductance (A-g s) was evaluated to estimate leaf stomatal conductance of a drip-irrigated vineyard (Vitis vinifera L. cv. Cabernet Sauvignon) located in the Pencahue Valley (35º22’ S, 71°47’ W, 150 m.a.s.l.), Maule Region, Chile, during the 2003-2004 and the 2004-2005 growing seasons. Additionally, a calibration of the three parameters mesophyll conductance (g m), maximum specific humidity (Dmax) and coupled factor (f0) was applied on vines growing in 35 L pots. An infrared gas analyzer was used to calibrate and evaluate the A-g s which allowed simultaneous measuring of the leaf net CO2 assimilation (A) and stomatal conductance (g s) in 2 to 3 h intervals of time. The calibration indicated that the g m,,...
Tipo: Journal article
Palavras-chave: A-g s model; Photosynthesis; Mesophyll conductance; Stem water potential; Sensitivity analysis.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100011

Physiological Dose-Response of Coffee (Coffea arabica L.) Plants to Glyphosate Depends on Growth Stage
Provedor de dados: 117
Autores: de Carvalho,Leonardo Bianco; Aguiar Alves,Pedro Luis da Costa; Bianco,Silvano; De Prado,Rafael.
Glyphosate is the main herbicide used in coffee (Coffea arabica L.) plantations in Brazil. Problems with herbicide drift commonly occur in orchard fields due to non-adequate spraying conditions. A series of experiments was carried out aiming to evaluate physiological dose-response of C. arabica plants submitted to exposure to simulated glyphosate drift in two distinct plant growth stages. Glyphosate was applied at 0, 180, 360, and 720 g acid equivalent (AE) ha-1 directly on coffee plants with 10 and 45 d after transplanting (DAT). Glyphosate doses in a range of 180-360 g AE ha-1 increased photosynthesis, transpiration and stomatal conductance in 10 DAT-plants up to 14 d after application (DAA) while, in 45 DAT-plants, an increase was observed only up to 2...
Tipo: Journal article
Palavras-chave: N-(phosphonomethyl) glycine; Herbicide drift; Photosynthesis; Plant nutrition.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200003

Exploring the Potential use of Photo-Selective Nets for Fruit Growth Regulation in Apple
Provedor de dados: 117
Autores: Bastías,Richard M; Manfrini,Luigi; Corelli Grappadelli,Luca.
The effect of shading (i.e. reduction of sunlight availability) on fruit growth physiology has been widely studied in apple (Malus domestica Borkh.), but little knowledge exist about fruit growth responses to changes in the light spectrum. The aim of the present research was to study the effect of use of colored nets with differential sunlight transmission in the blue (B, 400-500 nm), red (R, 600-700 nm) and far-red (FR, 700-800 nm) spectra on apple fruit growth and physiological associated responses. Three year old 'Fuji' apple trees were covered with 40% photo-selective blue and red shade nets, 40% neutral grey shade net, and 20% neutral white net as control. Red and blue net reduced in the same proportion (27%) the photosynthetically active radiation...
Tipo: Journal article
Palavras-chave: Sunlight spectrum management; Fruit size; Photosynthesis; Morphogenesis.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200010

Influence of double cropping on growth and yield of dry beans with colored plastic mulches
Provedor de dados: 117
Autores: Ibarra-Jiménez,Luis; Valdez-Aguilar,Luis Alonso; Cárdenas-Flores,Antonio; Lira-Saldivar,Hugo; Lozano-del Río,Javier; Lozano Cavazos,Carlos.
There are numerous studies of the use of plastic mulches in vegetable production, but there is little documentation of their use with dry beans (Phaseolus vulgaris L.) in single and double cropping. The objective of this study was to grow dry beans over two consecutive growing seasons using the same plastic mulch of different colors and examine the influence of soil temperature on growth and yield. The experiment was conducted in Saltillo, Coahuila, Mexico, in the spring and summer of 2008. The treatments included four colored plastic mulches: white-on-black, black, silver-on-black, aluminum-on-black, and bare soil as a control. The experimental design was a randomized complete block with four replicates. The percentage of photosynthetically active...
Tipo: Journal article
Palavras-chave: Phaseolus vulgaris; Soil temperature; Photosynthesis; PAR; Plasticulture.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400002

The physiological and growth response of Acacia caven under water stress and the application of different levels of biosolids
Provedor de dados: 118
Autores: Donoso,Sergio; Peña-Rojas,Karen; Pacheco,Cristian; Durán,Sergio; Santelices,Rómulo; Mascaró,Cristóbal.
Acacia caven (Mol.) Mol. (Leguminosae), generally known as "espino," is one of the most common tree species in the Mediterranean region of Chile. This species grows in nutritionally poor soils with low water availability during the summer, so it is very difficult for new seedlings to become established. To investigate the effects of water restriction and the potential benefit of the application of biosolids (sludge bio-dried to 25% moisture) on the growth of the plant, a completely random, two x three factorial design was carried out in controlled nursery conditions under two irrigation regimes (well-watered plants and controlled water restriction) and three biosolid application rates (0:100, 10:90 and 20:80) in a clay substrate. Physiological evaluations...
Tipo: Journal article
Palavras-chave: Biomass; Predawn water potential; Photosynthesis; Shoot:root ratio; Water restriction.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202015000200013

Climate change and agroecosystems: the effect of elevated atmospheric CO2 and temperature on crop growth, development, and yield
Provedor de dados: 65
Autores: Streck,Nereu Augusto.
The amount of carbon dioxide (CO2) of the Earth´s atmosphere is increasing, which has the potential of increasing greenhouse effect and air temperature in the future. Plants respond to environment CO2 and temperature. Therefore, climate change may affect agriculture. The purpose of this paper was to review the literature about the impact of a possible increase in atmospheric CO2 concentration and temperature on crop growth, development, and yield. Increasing CO2 concentration increases crop yield once the substrate for photosynthesis and the gradient of CO2 concentration between atmosphere and leaf increase. C3 plants will benefit more than C4 plants at elevated CO2. However, if global warming will take place, an increase in temperature may offset the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Global warming; Photosynthesis; Agriculture; Food supply.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782005000300041

Productivity and drought tolerance of cassava cultivars in the Coastal Tablelands of Northeastern Brazil
Provedor de dados: 65
Autores: Carvalho,Luciana Marques de; Carvalho,Hélio Wilson Lemos de; Oliveira,Ivênio Rubens de; Rangel,Marco Antônio Sedrez; Santos,Vanderlei da Silva.
ABSTRACT: Ten cassava cultivars were grown in the field and evaluated to identify the most adapted to the Coastal Tablelands of northeast Brazil. The cultivars showed differences in proline and chlorophyll contents, plant height, number of leaves and branches, canopy area and root production, however they did not differ on photosynthetic rates. Cultivars 'Tianguá' and '9783-13' presented lower root yield, whereas 'BRS Tapioqueira' and 'Irará' had the highest root yield. Few leaves coupled with the highest water use efficiency for CO2 assimilation was found in 'BRS Kiriris' in contrast to 'BRS Jarina' and '9783-13'. 'BRS Caipira' had high proline content in both Umbaúba and Frei Paulo areas, traits usually associated to drought tolerance, that contribute to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Manihot esculenta; Adaptation; Osmotic adjustment; Photosynthesis; Chlorophyll.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782016000500796

The sensitivity of sunflower (Helianthus annuus L.) plants to UV-B radiation is altered by nitrogen status
Provedor de dados: 65
Autores: Cechin,Inês; Gonzalez,Gisely Cristina; Corniani,Natália; Fumis,Terezinha de Fátima.
ABSTRACT: Interaction effects between nitrogen and UV-B radiation were studied in sunflower (Helianthus annuus L. variety IAC-Iarama) plants grown in a greenhouse under natural photoperiod conditions. Plants were irradiated with 0.8W m-2 (control) or 8.0W m-2 (+UV-B) of UV-B radiation for 7h per day. The plants were grown in pots containing vermiculite and watered with 70% of full strength nitrogen-free Long Ashton solution, containing either low (42.3ppm) or high (282ppm) nitrogen as ammonium nitrate. High nitrogen increased dry matter of stem, leaves and shoot, photosynthetic pigments and photosynthesis (A) without any alteration in stomatal conductance (gs) nor transpiration (E) while it reduced the intercellular CO2 (Ci) concentration, and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antioxidants; Growth; Malondialdehyde; Peroxidation; Photosynthesis.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782018000200251

Serpentine leafminer (Liriomyza trifolii) on potato (Solanum tuberosum): field observations and plant photosynthetic responses to injury
Provedor de dados: 65
Autores: Bueno,Adeney de Freitas; Zechmann,Benjamin; Hoback,William Wyatt; Bueno,Regiane Cristina Oliveira de Freitas; Fernandes,Odair Aparecido.
Serpentine leafminers, Liriomyza spp. (Diptera: Agromyzidae), are polyphagous insects that feed on numerous crops worldwide including potato. Recently, leafminer larvae (Liriomyza trifolii) have become an economically important pest of potato. The larvae eat the mesophyll of leaflets leaving long winding tunnels inside the leaflets. The photosynthetic effects of larval tunneling on the remaining leaf tissue are unknown. In 2003, physiological responses of potato to leafminer, L. trifolii were evaluated in Kearney, Nebraska, USA. The leaflets were examined 7 and 14 days post infestation for leaf area injury, photosynthetic rates and fluorescence. Leafminers caused up to 13% leaf area loss due to leafminer injury with no effect on the photosynthetic rates of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Plant-insect interaction; Chemical control; Photosynthesis.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782007000600001

Photosynthetic index and nitrogen assimilation in rapeseed seedlings transplanted in soil with ammonium glufosinate
Provedor de dados: 65
Autores: Cui,Cui; Xie,Xurong; Wang,Liu-Yan; Wang,Rui-Li; Lei,Wei; Lv,Jun; Chen,Liuyi; Gao,Huan-Huan; Ye,Sang; Huang,Linya; Zhou,Qing-Yuan.
ABSTRACT: Herbicide application is an effective weed control method for mitigating crop yield loss; however, herbicide overuse can cause toxicity in non-target plants. The present study evaluated the effects of glufosinate at recommended dose for agricultural application (0.45 kg ha-1) and at overuse dose (0.90 kg ha-1) glufosinate application on photosynthetic performance and nitrogen assimilation of the rapeseed varieties D148 and Zhongshuang 11 (ZS11). Both glufosinate concentrations significantly decreased the content of chlorophyll and nitrogenous compounds, except free proline, and the activity of glutamine synthetase and glutamate synthase, and increased the activity of glutamic acid dehydrogenase in both varieties. When the concentration of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Residual glufosinate; Rapeseed; Seedling transplanted; Photosynthesis; Nitrogen assimilation.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782020000400251

Differential responses between mature and young leaves of sunflower plants to oxidative stress caused by water deficit
Provedor de dados: 65
Autores: Cechin,Inês; Corniani,Natália; Fumis,Terezinha de Fátima; Cataneo,Ana Catarina.
The effects of water stress and rehydration on leaf gas exchange characteristics along with changes in lipid peroxidation and pirogalol peroxidase (PG-POD) were studied in mature and in young leaves of sunflower (Helianthus annuus L.), which were grown in a greenhouse. Water stress reduced photosynthesis (Pn), stomatal conductance (g s), and transpiration (E) in both young and mature leaves. However, the amplitude of the reduction was dependent on leaf age. The intercellular CO2 concentration (Ci) was increased in mature leaves but it was not altered in young leaves. Instantaneous water use efficiency (WUE) in mature stressed leaves was reduced when compared to control leaves while in young stressed leaves it was maintained to the same level as the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Antioxidant enzymes; Lipid peroxidation; Rehydration; Helianthus annuus.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782010000600008

Tolerance to water deficiency between two soybean cultivars: transgenic versus conventional
Provedor de dados: 65
Autores: Catuchi,Tiago Aranda; Vítolo,Hílton Fabrício; Bertolli,Suzana Chiari; Souza,Gustavo Maia.
The main goal of the study was to evaluate the effects on the development and physiological aspects of soybean plants grown under water deficiency at greenhouse conditions, comparing the levels of tolerance to water deficiency between one transgenic and one conventional cultivar, enabling a systematic way to carried out physiological comparisons between soybean cultivars under drought. The study was divided into completely randomized using a factorial 2×2 design, with five replicates. The experimental design included two replenishment levels of daily irrigation (100% and 40%), applied to the leaves during the V4 developmental stage (fourth trifoliate fully expanded) and two cultivars, 'CD 202' conventional and 'CD 226RR' transgenic. The results showed that...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Drought; Glycine max; Photosynthesis; Water relations.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782011000300002

Forage yield, rate of CO 2 assimilation, and quality of temperate annual forage species grown under artificial shading conditions
Provedor de dados: 65
Autores: Soares,André Brugnara; Bernardon,Angela; Aiolfi,Ricardo Beffart.
ABSTRACT: In this study, it was evaluated the effect of shade on forage yield, rate of CO2 assimilation, and the quality of annual ryegrass ( Lolium multiflorum L.) cv. 'BRS Ponteio' and black oat ( Avena strigosa Schreb) cv. 'IAPAR 61', grown under three shading conditions (0%, 25%, and 50% shade) using slatted wooden structures. The experimental design was completely randomized with four replications. Slatted structures were efficient in simulating the proposed shading conditions. Shading plants significantly decreased forage yield and CO2 assimilation by both species. Ryegrass cv. 'BRS Ponteio' performed better under shade, with higher forage production under all shading conditions. Rate of CO2 assimilation was reduced by 13 and 22 percentage points...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Grass; Light restriction; Photosynthesis; Silvopastoral system.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782016000601064

Growth and physiological responses of sunflower plants exposed to ultraviolet-B radiation
Provedor de dados: 65
Autores: Cechin,Inês; Fumis,Terezinha de Fátima; Dokkedal,Anne Ligia.
The effects of UV-B radiation were studied in sunflower plants (Helianthus annuus L. cv. Catissol-01) growning in greenhouse under natural photoperiod conditions. The plants received approximately 0.60Wm-2 (control) or 4.0Wm-2 (+UV-B) of UV-B radiation for 7h d-1, centered around solar noon from 15 days after sowing. Compared to the control, plants exposed to high UV-B radiation for 12 or 21 days did not show any difference in shoot dry matter, specific leaf weight or UV-B absorbing compounds. Enhanced UV-B radiation caused a significant inhibition of photosynthesis (A) only in the first sampling and this was accompained by reduction in stomatal conductance (g s) and transpiration rate. The inhibition in A can not be fully explained by reduction in g s...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Growth; Helianthus annuus; Phenolics; Photosynthesis.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782007000100014

Relationship between root exudation of organic carbon and physiological variables of irrigated rice cultivars
Provedor de dados: 65
Autores: Moscôso,Janielly Silva Costa; Silva,Leandro Souza da; Tarouco,Camila Peligrinotti; Nicoloso,Fernando Teixeira; Severo,Fabiane Figueiredo; Aita,Natália Tobin; Prigol,Luís Henrique Ferreira.
ABSTRACT:  Rhizospheric carbon resulting from root exudation is one of the substrates used by the soil microbiota, and reflects methane (CH4) emissions in anoxic environments such as irrigated rice cultivation. With the increase of the photosynthetic capacity of the plant in the reproductive period, there is greater accumulation of biomass which, in turn, increases the rate of root exudation. However, genotypic variations in the physiological aspects of rice plants may be related to the amount of root exudates. Ten cultivars of irrigated rice were evaluated for the exudation rate of total organic carbon (EXRToc), shoot dry matter (SDM), and physiological variables related to photosynthesis during the full flowering (blooming) period. Two experiments were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oryza sativa; Photosynthesis; Exudates; Methanogenesis.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782018001200250

Photosynthetic capacity of 'Niagara Rosada' grapes grown under transparent plastic covering
Provedor de dados: 65
Autores: Deus,Bruna Corrêa da Silva de; Figueiredo,Fábio Afonso Mazzei Moura de Assis; Almeida,Luciana Venturotti Braun de; Ferraz,Tiago Massi; Martins,Amanda Oliveira; Rodrigues,Weverton Pereira; Viana,Leandro Hespanhol; Esteves,Barbara dos Santos; Campostrini,Eliemar.
ABSTRACT: New techniques in tropical regions such as use of transparent plastic covering (TPC), have been employed in grapes to avoid the wetting leaves and fruits, which can reduce the occurrence of fungal diseases, reduce the use of sprays, and reduce damage caused by hail and high winds. TPC may significantly affect the photosynthetic rates of grapevines cultivated in tropical regions, and thus have strong effects on plant productivity and improve fruit quality. However, in the North of Rio de Janeiro region there are lacks of studies related to TPC effects on photosynthetic capacity. The objective of this study was to evaluate the photosynthetic capacity in 'Niagara Rosada' vines grown under TPC and without transparent plastic covering (WTPC). The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Chlorophyll fluorescence; Vitisla brusca; Covered system.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782016000600950

Morpho-physiological changes in pineapple plantlets [Ananas comosus (L.) merr.] during acclimatization
Provedor de dados: 64
Autores: Villalobo,Ariel; González,Justo; Santos,Ramón; Rodríguez,Romelio.
Pineapple producing countries lack good quality propagation material to expand cultivars into new areas. Previously, research protocols may increase the offer of high quality plantlets and speed the introduction of new pineapple cultivars. The present work is to evaluate the morpho-physiological changes in plantlets of pineapple [Ananas comosus (L.) Merr. 'MD-2'] during the acclimatization phase. Plantlets were acclimatized under 80% relative humidity, 25.5 °C temperature and photosynthetic photon flux of 400-500 µmol m-2 s-1 as average for 45 d under natural photoperiods. All measurements (plant length, number of leaves and roots, fresh weight, width and length of leaf 'D', net photosynthesis and total transpiration rate) were carried out at the end of in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chlorophyll; Ex vitro conditions; Photosynthesis; Transpiration.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542012000600004

Hydrogen sulfide, potassium phosphite and zinc sulfate as alleviators of drought stress in sunflower plants
Provedor de dados: 64
Autores: Almeida,Gabriel Martins; Silva,Adinan Alves da; Batista,Priscila Ferreira; Moura,Luciana Minervina de Freitas; Vital,Roberto Gomes; Costa,Alan Carlos.
ABSTRACT Drought is the most harmful environmental factor crop productivity. Some chemicals are used in agriculture to mitigate the damage from this stress on plants. Therefore, we examined whether the spraying of zinc sulfate (ZS), potassium phosphite (KPhi) and the hydrogen sulfide (H2S) donor sodium hydrosulfide (NaHS) would mitigate the deleterious effects of water deficit on sunflower plants by analyzing physiological and biometric characteristics. The experiment was carried out in a greenhouse using a randomized block design with five replications. The treatments were arranged in a 4 x 2 factorial scheme: [Factor A (Alleviators)] - spraying of KPhi (0.5 L ha-1), ZS (3.2 kg ha-1), NaHS (1.2 g ha-1), and water; [Factor B (substrate humidity, SH)] -...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photosynthesis; Water deficit; Malonaldehyde; Leaf water potential; Mitigating substance.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542020000100225

GAS EXCHANGE AND CARBOHYDRATE PARTITIONING IN COFFEE SEEDLINGS UNDER WATERLOGGING
Provedor de dados: 64
Autores: Silveira,Helbert Rezende de Oliveira; Souza,Kamila Rezende Dázio de; Alves,Jose Donizeti; Santos,Meline de Oliveira; Andrade,Cínthia Aparecida; Bomfim,Sandro Costa.
Irrigation has enhanced coffee production in several regions of Brazil. However, with the increase in irrigated crop areas, problems related to the frequent and poorly planned usage of irrigation may arise. Since there are few studies related to the physiological alterations in coffee plants exposed to water excess, we evaluated the effects of waterlogging on metabolism and partitioning of carbohydrates, levels of photosynthetic pigments and gas exchange in seedlings of two commercial coffee cultivars (Mundo Novo and Catuaí). After acclimation, seedlings with eight pairs of fully expanded leaves were cultivated under three water availability conditions: field capacity, intermittent waterlogging and continuous waterlogging. Gas exchange and the levels of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Water excess; Photosynthesis; Reducing sugars; Stomatal conductance; Water efficiency use.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542015000200138

Photosynthetic behaviour during the leaf ontogeny of rubber tree clones[Hevea brasiliensis (Wild. ex. Adr. de Juss.) Muell. Arg.], in Lavras, MG
Provedor de dados: 64
Autores: Miguel,Aurélio Antas; Oliveira,Luiz Edson Mota de; Cairo,Paulo Araquém Ramos; Oliveira,Davi Melo de.
This work proposed to investigate changes in the photosynthetic behavior during the leaf ontogeny of the during the leaf development. Up to the 32nd day of leaf age (stage B2), the net photosynthesis was negative due to the inefficiency of the photosynthetic system, and this fact was justified by the following factors: low chlorophyll content, less stomatal conductance, high rubber tree clones PB 235, RRIM 600 and GT 1, in Lavras, MG. The experiment was performed in 2004, between May and July, under field conditions, at the Universidade Federal de Lavras. During the leaf ontogeny, the following characteristics were evaluated: chlorophyll content, gaseous exchanges and chlorophyll fluorescence. The clones presented similar profiles of alterations in the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Rubber tree; Photosynthesis; Gaseous exchanges; Chlorophyll fluorescence.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542007000100014